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LibrePilot/flight/pios/common/pios_rfm22b.c
Karl Knutsson 9fd4fb26b9 OP-1532 fix non-ppm mode
Always send packets from the coordinator.
Previously the coordinator only always sent packets
on channel 0. This scheme doesn't work with
with the change to use 32 channel.
2014-10-08 20:59:51 +02:00

2567 lines
90 KiB
C
Raw Blame History

/**
******************************************************************************
* @addtogroup PIOS PIOS Core hardware abstraction layer
* @{
* @addtogroup PIOS_RFM22B Radio Functions
* @brief PIOS interface for for the RFM22B radio
* @{
*
* @file pios_rfm22b.c
* @author The OpenPilot Team, http://www.openpilot.org Copyright (C) 2012.
* @brief Implements a driver the the RFM22B driver
* @see The GNU Public License (GPL) Version 3
*
*****************************************************************************/
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
// *****************************************************************
// RFM22B hardware layer
//
// This module uses the RFM22B's internal packet handling hardware to
// encapsulate our own packet data.
//
// The RFM22B internal hardware packet handler configuration is as follows:
//
// 6-byte (32-bit) preamble .. alternating 0's & 1's
// 4-byte (32-bit) sync
// 1-byte packet length (number of data bytes to follow)
// 0 to 255 user data bytes
// 4 byte ECC
//
// OR in PPM only mode:
//
// 6-byte (32-bit) preamble .. alternating 0's & 1's
// 4-byte (32-bit) sync
// 1-byte packet length (number of data bytes to follow)
// 1 byte valid bitmask
// 8 PPM values (0-255)
// 1 byte CRC
//
// *****************************************************************
#include "pios.h"
#ifdef PIOS_INCLUDE_RFM22B
#include <pios_spi_priv.h>
#include <pios_rfm22b_priv.h>
#include <pios_ppm_out.h>
#include <ecc.h>
/* Local Defines */
#define STACK_SIZE_BYTES 200
#define TASK_PRIORITY (tskIDLE_PRIORITY + 4) // flight control relevant device driver (ppm link)
#define ISR_TIMEOUT 1 // ms
#define EVENT_QUEUE_SIZE 5
#define RFM22B_DEFAULT_RX_DATARATE RFM22_datarate_9600
#define RFM22B_DEFAULT_TX_POWER RFM22_tx_pwr_txpow_0
#define RFM22B_NOMINAL_CARRIER_FREQUENCY 430000000
#define RFM22B_LINK_QUALITY_THRESHOLD 20
#define RFM22B_DEFAULT_MIN_CHANNEL 0
#define RFM22B_DEFAULT_MAX_CHANNEL 250
#define RFM22B_DEFAULT_CHANNEL_SET 24
#define RFM22B_PPM_ONLY_DATARATE RFM22_datarate_9600
// The maximum amount of time without activity before initiating a reset.
#define PIOS_RFM22B_SUPERVISOR_TIMEOUT 150 // ms
// this is too adjust the RF module so that it is on frequency
#define OSC_LOAD_CAP 0x7F // cap = 12.5pf .. default
#define TX_PREAMBLE_NIBBLES 12 // 7 to 511 (number of nibbles)
#define RX_PREAMBLE_NIBBLES 6 // 5 to 31 (number of nibbles)
#define SYNC_BYTES 4
#define HEADER_BYTES 4
#define LENGTH_BYTES 1
// the size of the rf modules internal FIFO buffers
#define FIFO_SIZE 64
#define TX_FIFO_HI_WATERMARK 62 // 0-63
#define TX_FIFO_LO_WATERMARK 32 // 0-63
#define RX_FIFO_HI_WATERMARK 32 // 0-63
// preamble byte (preceeds SYNC_BYTE's)
#define PREAMBLE_BYTE 0x55
// RF sync bytes (32-bit in all)
#define SYNC_BYTE_1 0x2D
#define SYNC_BYTE_2 0xD4
#define SYNC_BYTE_3 0x4B
#define SYNC_BYTE_4 0x59
#ifndef RX_LED_ON
#define RX_LED_ON
#define RX_LED_OFF
#define TX_LED_ON
#define TX_LED_OFF
#define LINK_LED_ON
#define LINK_LED_OFF
#define USB_LED_ON
#define USB_LED_OFF
#endif
#define CONNECTED_LIVE 8
/* Local type definitions */
struct pios_rfm22b_transition {
enum pios_radio_event (*entry_fn)(struct pios_rfm22b_dev *rfm22b_dev);
enum pios_radio_state next_state[RADIO_EVENT_NUM_EVENTS];
};
// Must ensure these prefilled arrays match the define sizes
static const uint8_t FULL_PREAMBLE[FIFO_SIZE] = {
PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE,
PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE,
PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE,
PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE,
PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE,
PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE,
PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE,
PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE,
PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE,
PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE,
PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE,
PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE,
PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE
}; // 64 bytes
static const uint8_t HEADER[(TX_PREAMBLE_NIBBLES + 1) / 2 + 2] = {
PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, PREAMBLE_BYTE, SYNC_BYTE_1, SYNC_BYTE_2
};
static const uint8_t OUT_FF[64] = {
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF
};
// The randomized channel list.
static const uint8_t channel_list[] = {
68, 34, 2, 184, 166, 94, 204, 18, 47, 118, 239, 176, 5, 213, 218, 186, 104, 160, 199, 209, 231, 197, 92,
191, 88, 129, 40, 19, 93, 200, 156, 14, 247, 182, 193, 194, 208, 210, 248, 76, 244, 48, 179, 105, 25, 74,
155, 203, 39, 97, 195, 81, 83, 180, 134, 172, 235, 132, 198, 119, 207, 154, 0, 61, 140, 171, 245, 26, 95,
3, 22, 62, 169, 55, 127, 144, 45, 33, 170, 91, 158, 167, 63, 201, 41, 21, 190, 51, 103, 49, 189, 205,
240, 89, 181, 149, 6, 157, 249, 230, 115, 72, 163, 17, 29, 99, 28, 117, 219, 73, 78, 53, 69, 216, 161,
124, 110, 242, 214, 145, 13, 11, 220, 113, 138, 58, 54, 162, 237, 37, 152, 187, 232, 77, 126, 85, 38, 238,
173, 23, 188, 100, 131, 226, 31, 9, 114, 106, 221, 42, 233, 139, 4, 241, 96, 211, 8, 98, 121, 147, 24,
217, 27, 87, 122, 125, 135, 148, 178, 71, 206, 57, 141, 35, 30, 246, 159, 16, 32, 15, 229, 20, 12, 223,
150, 101, 79, 56, 102, 111, 174, 236, 137, 143, 52, 225, 64, 224, 112, 168, 243, 130, 108, 202, 123, 146, 228,
75, 46, 153, 7, 192, 175, 151, 222, 59, 82, 90, 1, 65, 109, 44, 165, 84, 43, 36, 128, 196, 67, 80,
136, 86, 70, 234, 66, 185, 10, 164, 177, 116, 50, 107, 183, 215, 212, 60, 227, 133, 120, 14
};
/* Local function forwared declarations */
static void pios_rfm22_task(void *parameters);
static bool pios_rfm22_readStatus(struct pios_rfm22b_dev *rfm22b_dev);
static void pios_rfm22_setDatarate(struct pios_rfm22b_dev *rfm22b_dev);
static void rfm22_rxFailure(struct pios_rfm22b_dev *rfm22b_dev);
static void pios_rfm22_inject_event(struct pios_rfm22b_dev *rfm22b_dev, enum pios_radio_event event, bool inISR);
static enum pios_radio_event rfm22_init(struct pios_rfm22b_dev *rfm22b_dev);
static enum pios_radio_event radio_setRxMode(struct pios_rfm22b_dev *rfm22b_dev);
static enum pios_radio_event radio_rxData(struct pios_rfm22b_dev *rfm22b_dev);
static enum pios_radio_event radio_receivePacket(struct pios_rfm22b_dev *rfm22b_dev, uint8_t *p, uint16_t rx_len);
static enum pios_radio_event radio_txStart(struct pios_rfm22b_dev *rfm22b_dev);
static enum pios_radio_event radio_txData(struct pios_rfm22b_dev *rfm22b_dev);
static enum pios_radio_event rfm22_txFailure(struct pios_rfm22b_dev *rfm22b_dev);
static enum pios_radio_event rfm22_process_state_transition(struct pios_rfm22b_dev *rfm22b_dev, enum pios_radio_event event);
static void rfm22_process_event(struct pios_rfm22b_dev *rfm22b_dev, enum pios_radio_event event);
static enum pios_radio_event rfm22_timeout(struct pios_rfm22b_dev *rfm22b_dev);
static enum pios_radio_event rfm22_error(struct pios_rfm22b_dev *rfm22b_dev);
static enum pios_radio_event rfm22_fatal_error(struct pios_rfm22b_dev *rfm22b_dev);
static void rfm22b_add_rx_status(struct pios_rfm22b_dev *rfm22b_dev, enum pios_rfm22b_rx_packet_status status);
static void rfm22_setNominalCarrierFrequency(struct pios_rfm22b_dev *rfm22b_dev, uint8_t init_chan);
static bool rfm22_setFreqHopChannel(struct pios_rfm22b_dev *rfm22b_dev, uint8_t channel);
static void rfm22_updatePairStatus(struct pios_rfm22b_dev *radio_dev);
static void rfm22_calculateLinkQuality(struct pios_rfm22b_dev *rfm22b_dev);
static bool rfm22_isConnected(struct pios_rfm22b_dev *rfm22b_dev);
static bool rfm22_isCoordinator(struct pios_rfm22b_dev *rfm22b_dev);
static uint32_t rfm22_destinationID(struct pios_rfm22b_dev *rfm22b_dev);
static bool rfm22_timeToSend(struct pios_rfm22b_dev *rfm22b_dev);
static void rfm22_synchronizeClock(struct pios_rfm22b_dev *rfm22b_dev);
static portTickType rfm22_coordinatorTime(struct pios_rfm22b_dev *rfm22b_dev, portTickType ticks);
static uint8_t rfm22_calcChannel(struct pios_rfm22b_dev *rfm22b_dev, uint8_t index);
static uint8_t rfm22_calcChannelFromClock(struct pios_rfm22b_dev *rfm22b_dev);
static bool rfm22_changeChannel(struct pios_rfm22b_dev *rfm22b_dev);
static void rfm22_clearLEDs();
// Utility functions.
static uint32_t pios_rfm22_time_difference_ms(portTickType start_time, portTickType end_time);
static struct pios_rfm22b_dev *pios_rfm22_alloc(void);
// SPI read/write functions
static void rfm22_assertCs(struct pios_rfm22b_dev *rfm22b_dev);
static void rfm22_deassertCs(struct pios_rfm22b_dev *rfm22b_dev);
static void rfm22_claimBus(struct pios_rfm22b_dev *rfm22b_dev);
static void rfm22_releaseBus(struct pios_rfm22b_dev *rfm22b_dev);
static void rfm22_write_claim(struct pios_rfm22b_dev *rfm22b_dev, uint8_t addr, uint8_t data);
static void rfm22_write(struct pios_rfm22b_dev *rfm22b_dev, uint8_t addr, uint8_t data);
static uint8_t rfm22_read(struct pios_rfm22b_dev *rfm22b_dev, uint8_t addr);
/* The state transition table */
static const struct pios_rfm22b_transition rfm22b_transitions[RADIO_STATE_NUM_STATES] = {
// Initialization thread
[RADIO_STATE_UNINITIALIZED] = {
.entry_fn = 0,
.next_state = {
[RADIO_EVENT_INITIALIZE] = RADIO_STATE_INITIALIZING,
[RADIO_EVENT_ERROR] = RADIO_STATE_ERROR,
},
},
[RADIO_STATE_INITIALIZING] = {
.entry_fn = rfm22_init,
.next_state = {
[RADIO_EVENT_INITIALIZED] = RADIO_STATE_RX_MODE,
[RADIO_EVENT_ERROR] = RADIO_STATE_ERROR,
[RADIO_EVENT_INITIALIZE] = RADIO_STATE_INITIALIZING,
[RADIO_EVENT_FATAL_ERROR] = RADIO_STATE_FATAL_ERROR,
},
},
[RADIO_STATE_RX_MODE] = {
.entry_fn = radio_setRxMode,
.next_state = {
[RADIO_EVENT_INT_RECEIVED] = RADIO_STATE_RX_DATA,
[RADIO_EVENT_TX_START] = RADIO_STATE_TX_START,
[RADIO_EVENT_RX_MODE] = RADIO_STATE_RX_MODE,
[RADIO_EVENT_TIMEOUT] = RADIO_STATE_TIMEOUT,
[RADIO_EVENT_ERROR] = RADIO_STATE_ERROR,
[RADIO_EVENT_INITIALIZE] = RADIO_STATE_INITIALIZING,
[RADIO_EVENT_FATAL_ERROR] = RADIO_STATE_FATAL_ERROR,
},
},
[RADIO_STATE_RX_DATA] = {
.entry_fn = radio_rxData,
.next_state = {
[RADIO_EVENT_INT_RECEIVED] = RADIO_STATE_RX_DATA,
[RADIO_EVENT_TX_START] = RADIO_STATE_TX_START,
[RADIO_EVENT_RX_COMPLETE] = RADIO_STATE_TX_START,
[RADIO_EVENT_RX_MODE] = RADIO_STATE_RX_MODE,
[RADIO_EVENT_TIMEOUT] = RADIO_STATE_TIMEOUT,
[RADIO_EVENT_ERROR] = RADIO_STATE_ERROR,
[RADIO_EVENT_INITIALIZE] = RADIO_STATE_INITIALIZING,
[RADIO_EVENT_FATAL_ERROR] = RADIO_STATE_FATAL_ERROR,
},
},
[RADIO_STATE_TX_START] = {
.entry_fn = radio_txStart,
.next_state = {
[RADIO_EVENT_INT_RECEIVED] = RADIO_STATE_TX_DATA,
[RADIO_EVENT_RX_MODE] = RADIO_STATE_RX_MODE,
[RADIO_EVENT_TIMEOUT] = RADIO_STATE_TIMEOUT,
[RADIO_EVENT_ERROR] = RADIO_STATE_ERROR,
[RADIO_EVENT_INITIALIZE] = RADIO_STATE_INITIALIZING,
[RADIO_EVENT_FATAL_ERROR] = RADIO_STATE_FATAL_ERROR,
},
},
[RADIO_STATE_TX_DATA] = {
.entry_fn = radio_txData,
.next_state = {
[RADIO_EVENT_INT_RECEIVED] = RADIO_STATE_TX_DATA,
[RADIO_EVENT_RX_MODE] = RADIO_STATE_RX_MODE,
[RADIO_EVENT_TIMEOUT] = RADIO_STATE_TIMEOUT,
[RADIO_EVENT_ERROR] = RADIO_STATE_ERROR,
[RADIO_EVENT_INITIALIZE] = RADIO_STATE_INITIALIZING,
[RADIO_EVENT_FATAL_ERROR] = RADIO_STATE_FATAL_ERROR,
},
},
[RADIO_STATE_TX_FAILURE] = {
.entry_fn = rfm22_txFailure,
.next_state = {
[RADIO_EVENT_TX_START] = RADIO_STATE_TX_START,
[RADIO_EVENT_TIMEOUT] = RADIO_STATE_TIMEOUT,
[RADIO_EVENT_ERROR] = RADIO_STATE_ERROR,
[RADIO_EVENT_INITIALIZE] = RADIO_STATE_INITIALIZING,
[RADIO_EVENT_FATAL_ERROR] = RADIO_STATE_FATAL_ERROR,
},
},
[RADIO_STATE_TIMEOUT] = {
.entry_fn = rfm22_timeout,
.next_state = {
[RADIO_EVENT_TX_START] = RADIO_STATE_TX_START,
[RADIO_EVENT_RX_MODE] = RADIO_STATE_RX_MODE,
[RADIO_EVENT_ERROR] = RADIO_STATE_ERROR,
[RADIO_EVENT_INITIALIZE] = RADIO_STATE_INITIALIZING,
[RADIO_EVENT_FATAL_ERROR] = RADIO_STATE_FATAL_ERROR,
},
},
[RADIO_STATE_ERROR] = {
.entry_fn = rfm22_error,
.next_state = {
[RADIO_EVENT_INITIALIZE] = RADIO_STATE_INITIALIZING,
[RADIO_EVENT_FATAL_ERROR] = RADIO_STATE_FATAL_ERROR,
},
},
[RADIO_STATE_FATAL_ERROR] = {
.entry_fn = rfm22_fatal_error,
.next_state = {},
},
};
// xtal 10 ppm, 434MHz
static const uint32_t data_rate[] = {
9600, // 96 kbps, 433 HMz, 30 khz freq dev
19200, // 19.2 kbps, 433 MHz, 45 khz freq dev
32000, // 32 kbps, 433 MHz, 45 khz freq dev
57600, // 57.6 kbps, 433 MHz, 45 khz freq dev
64000, // 64 kbps, 433 MHz, 45 khz freq dev
100000, // 100 kbps, 433 MHz, 60 khz freq dev
128000, // 128 kbps, 433 MHz, 90 khz freq dev
192000, // 192 kbps, 433 MHz, 128 khz freq dev
256000, // 256 kbps, 433 MHz, 150 khz freq dev
};
static const uint8_t reg_1C[] = { 0x01, 0x05, 0x06, 0x95, 0x95, 0x81, 0x88, 0x8B, 0x8D }; // rfm22_if_filter_bandwidth
static const uint8_t reg_1D[] = { 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40 }; // rfm22_afc_loop_gearshift_override
static const uint8_t reg_1E[] = { 0x0A, 0x0A, 0x0A, 0x0A, 0x0A, 0x0A, 0x0A, 0x0A, 0x02 }; // rfm22_afc_timing_control
static const uint8_t reg_1F[] = { 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03 }; // rfm22_clk_recovery_gearshift_override
static const uint8_t reg_20[] = { 0xA1, 0xD0, 0x7D, 0x68, 0x5E, 0x78, 0x5E, 0x3F, 0x2F }; // rfm22_clk_recovery_oversampling_ratio
static const uint8_t reg_21[] = { 0x20, 0x00, 0x01, 0x01, 0x01, 0x01, 0x01, 0x02, 0x02 }; // rfm22_clk_recovery_offset2
static const uint8_t reg_22[] = { 0x4E, 0x9D, 0x06, 0x3A, 0x5D, 0x11, 0x5D, 0x0C, 0xBB }; // rfm22_clk_recovery_offset1
static const uint8_t reg_23[] = { 0xA5, 0x49, 0x25, 0x93, 0x86, 0x11, 0x86, 0x4A, 0x0D }; // rfm22_clk_recovery_offset0
static const uint8_t reg_24[] = { 0x00, 0x00, 0x01, 0x03, 0x03, 0x03, 0x03, 0x06, 0x07 }; // rfm22_clk_recovery_timing_loop_gain1
static const uint8_t reg_25[] = { 0x34, 0x88, 0x77, 0x29, 0xE2, 0x90, 0xE2, 0x1A, 0xFF }; // rfm22_clk_recovery_timing_loop_gain0
static const uint8_t reg_2A[] = { 0x1E, 0x24, 0x28, 0x3C, 0x3C, 0x50, 0x50, 0x50, 0x50 }; // rfm22_afc_limiter .. AFC_pull_in_range = <20>AFCLimiter[7:0] x (hbsel+1) x 625 Hz
static const uint8_t reg_58[] = { 0x80, 0x80, 0x80, 0x80, 0x80, 0xC0, 0xC0, 0xC0, 0xED }; // rfm22_cpcuu
static const uint8_t reg_69[] = { 0x60, 0x60, 0x60, 0x60, 0x60, 0x60, 0x60, 0x60, 0x60 }; // rfm22_agc_override1
static const uint8_t reg_6E[] = { 0x4E, 0x9D, 0x08, 0x0E, 0x10, 0x19, 0x20, 0x31, 0x41 }; // rfm22_tx_data_rate1
static const uint8_t reg_6F[] = { 0xA5, 0x49, 0x31, 0xBF, 0x62, 0x9A, 0xC5, 0x27, 0x89 }; // rfm22_tx_data_rate0
static const uint8_t reg_70[] = { 0x2C, 0x2C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C }; // rfm22_modulation_mode_control1
static const uint8_t reg_71[] = { 0x23, 0x23, 0x23, 0x23, 0x23, 0x23, 0x23, 0x23, 0x23 }; // rfm22_modulation_mode_control2
static const uint8_t reg_72[] = { 0x30, 0x48, 0x48, 0x48, 0x48, 0x60, 0x90, 0xCD, 0x0F }; // rfm22_frequency_deviation
static const uint8_t packet_time[] = { 80, 40, 25, 15, 13, 10, 8, 6, 5 };
static const uint8_t packet_time_ppm[] = { 26, 25, 25, 15, 13, 10, 8, 6, 5 };
static const uint8_t num_channels[] = { 32, 32, 32, 32, 32, 32, 32, 32, 32 };
static struct pios_rfm22b_dev *g_rfm22b_dev = NULL;
/*****************************************************************************
* External Interface Functions
*****************************************************************************/
/**
* Initialise an RFM22B device
*
* @param[out] rfm22b_id A pointer to store the device ID in.
* @param[in] spi_id The SPI bus index.
* @param[in] slave_num The SPI bus slave number.
* @param[in] cfg The device configuration.
*/
int32_t PIOS_RFM22B_Init(uint32_t *rfm22b_id, uint32_t spi_id, uint32_t slave_num, const struct pios_rfm22b_cfg *cfg)
{
PIOS_DEBUG_Assert(rfm22b_id);
PIOS_DEBUG_Assert(cfg);
// Allocate the device structure.
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)pios_rfm22_alloc();
if (!rfm22b_dev) {
return -1;
}
*rfm22b_id = (uint32_t)rfm22b_dev;
g_rfm22b_dev = rfm22b_dev;
// Store the SPI handle
rfm22b_dev->slave_num = slave_num;
rfm22b_dev->spi_id = spi_id;
// Initialize our configuration parameters
rfm22b_dev->datarate = RFM22B_DEFAULT_RX_DATARATE;
rfm22b_dev->tx_power = RFM22B_DEFAULT_TX_POWER;
rfm22b_dev->coordinator = false;
rfm22b_dev->coordinatorID = 0;
// Initialize the com callbacks.
rfm22b_dev->rx_in_cb = NULL;
rfm22b_dev->tx_out_cb = NULL;
// Initialzie the PPM callback.
rfm22b_dev->ppm_callback = NULL;
// Initialize the stats.
rfm22b_dev->stats.packets_per_sec = 0;
rfm22b_dev->stats.rx_good = 0;
rfm22b_dev->stats.rx_corrected = 0;
rfm22b_dev->stats.rx_error = 0;
rfm22b_dev->stats.rx_missed = 0;
rfm22b_dev->stats.tx_dropped = 0;
rfm22b_dev->stats.tx_resent = 0;
rfm22b_dev->stats.resets = 0;
rfm22b_dev->stats.timeouts = 0;
rfm22b_dev->stats.link_quality = 0;
rfm22b_dev->stats.rssi = 0;
rfm22b_dev->stats.tx_seq = 0;
rfm22b_dev->stats.rx_seq = 0;
rfm22b_dev->stats.tx_failure = 0;
// Initialize the channels.
PIOS_RFM22B_SetChannelConfig(*rfm22b_id, RFM22B_DEFAULT_RX_DATARATE, RFM22B_DEFAULT_MIN_CHANNEL,
RFM22B_DEFAULT_MAX_CHANNEL, RFM22B_DEFAULT_CHANNEL_SET, false, false, false, false);
// Create the event queue
rfm22b_dev->eventQueue = xQueueCreate(EVENT_QUEUE_SIZE, sizeof(enum pios_radio_event));
// Bind the configuration to the device instance
rfm22b_dev->cfg = *cfg;
// Create a semaphore to know if an ISR needs responding to
vSemaphoreCreateBinary(rfm22b_dev->isrPending);
// Create our (hopefully) unique 32 bit id from the processor serial number.
uint8_t crcs[] = { 0, 0, 0, 0 };
{
char serial_no_str[33];
PIOS_SYS_SerialNumberGet(serial_no_str);
// Create a 32 bit value using 4 8 bit CRC values.
for (uint8_t i = 0; serial_no_str[i] != 0; ++i) {
crcs[i % 4] = PIOS_CRC_updateByte(crcs[i % 4], serial_no_str[i]);
}
}
rfm22b_dev->deviceID = crcs[0] | crcs[1] << 8 | crcs[2] << 16 | crcs[3] << 24;
DEBUG_PRINTF(2, "RF device ID: %x\n\r", rfm22b_dev->deviceID);
// Initialize the external interrupt.
PIOS_EXTI_Init(cfg->exti_cfg);
// Register the watchdog timer for the radio driver task
#if defined(PIOS_INCLUDE_WDG) && defined(PIOS_WDG_RFM22B)
PIOS_WDG_RegisterFlag(PIOS_WDG_RFM22B);
#endif /* PIOS_WDG_RFM22B */
// Initialize the ECC library.
initialize_ecc();
// Set the state to initializing.
rfm22b_dev->state = RADIO_STATE_UNINITIALIZED;
// Initialize the radio device.
pios_rfm22_inject_event(rfm22b_dev, RADIO_EVENT_INITIALIZE, false);
// Start the driver task. This task controls the radio state machine and removed all of the IO from the IRQ handler.
xTaskCreate(pios_rfm22_task, "PIOS_RFM22B_Task", STACK_SIZE_BYTES, (void *)rfm22b_dev, TASK_PRIORITY, &(rfm22b_dev->taskHandle));
return 0;
}
/**
* Re-initialize the modem after a configuration change.
*
* @param[in] rbm22b_id The RFM22B device ID.
*/
void PIOS_RFM22B_Reinit(uint32_t rfm22b_id)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (PIOS_RFM22B_Validate(rfm22b_dev)) {
pios_rfm22_inject_event(rfm22b_dev, RADIO_EVENT_INITIALIZE, false);
}
}
/**
* The RFM22B external interrupt routine.
*/
bool PIOS_RFM22_EXT_Int(void)
{
if (!PIOS_RFM22B_Validate(g_rfm22b_dev)) {
return false;
}
// Inject an interrupt event into the state machine.
pios_rfm22_inject_event(g_rfm22b_dev, RADIO_EVENT_INT_RECEIVED, true);
return false;
}
/**
* Returns the unique device ID for the RFM22B device.
*
* @param[in] rfm22b_id The RFM22B device index.
* @return The unique device ID
*/
uint32_t PIOS_RFM22B_DeviceID(uint32_t rfm22b_id)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (PIOS_RFM22B_Validate(rfm22b_dev)) {
return rfm22b_dev->deviceID;
}
return 0;
}
/**
* Are we connected to the remote modem?
*
* @param[in] rfm22b_dev The device structure
*/
static bool rfm22_isConnected(struct pios_rfm22b_dev *rfm22b_dev)
{
return (rfm22b_dev->stats.link_state == OPLINKSTATUS_LINKSTATE_CONNECTED) || (rfm22b_dev->stats.link_state == OPLINKSTATUS_LINKSTATE_CONNECTING);
}
/**
* Returns true if the modem is not actively sending or receiving a packet.
*
* @param[in] rfm22b_id The RFM22B device index.
* @return True if the modem is not actively sending or receiving a packet.
*/
bool PIOS_RFM22B_InRxWait(uint32_t rfm22b_id)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (PIOS_RFM22B_Validate(rfm22b_dev)) {
return (rfm22b_dev->rfm22b_state == RFM22B_STATE_RX_WAIT) || (rfm22b_dev->rfm22b_state == RFM22B_STATE_TRANSITION);
}
return false;
}
/**
* Sets the radio device transmit power.
*
* @param[in] rfm22b_id The RFM22B device index.
* @param[in] tx_pwr The transmit power.
*/
void PIOS_RFM22B_SetTxPower(uint32_t rfm22b_id, enum rfm22b_tx_power tx_pwr)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (!PIOS_RFM22B_Validate(rfm22b_dev)) {
return;
}
rfm22b_dev->tx_power = tx_pwr;
}
/**
* Sets the range and number of channels to use for the radio.
* The channels are 0 to 255 divided across the 430-440 MHz range.
* The number of channels configured will be spread across the selected channel range.
* The channel spacing is 10MHz / 250 = 40kHz
*
* @param[in] rfm22b_id The RFM22B device index.
* @param[in] datarate The desired datarate.
* @param[in] min_chan The minimum channel.
* @param[in] max_chan The maximum channel.
* @param[in] chan_set The "seed" for selecting a channel sequence.
* @param[in] coordinator Is this modem an coordinator.
* @param[in] ppm_mode Should this modem send/receive ppm packets?
* @param[in] oneway Only the coordinator can send packets if true.
*/
void PIOS_RFM22B_SetChannelConfig(uint32_t rfm22b_id, enum rfm22b_datarate datarate, uint8_t min_chan, uint8_t max_chan, uint8_t chan_set, bool coordinator, bool oneway, bool ppm_mode, bool ppm_only)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (!PIOS_RFM22B_Validate(rfm22b_dev)) {
return;
}
ppm_mode = ppm_mode || ppm_only;
rfm22b_dev->coordinator = coordinator;
rfm22b_dev->ppm_send_mode = ppm_mode && coordinator;
rfm22b_dev->ppm_recv_mode = ppm_mode && !coordinator;
if (ppm_mode && (datarate <= RFM22B_PPM_ONLY_DATARATE)) {
ppm_only = true;
}
rfm22b_dev->ppm_only_mode = ppm_only;
if (ppm_only) {
rfm22b_dev->one_way_link = true;
datarate = RFM22B_PPM_ONLY_DATARATE;
rfm22b_dev->datarate = RFM22B_PPM_ONLY_DATARATE;
} else {
rfm22b_dev->one_way_link = oneway;
rfm22b_dev->datarate = datarate;
}
rfm22b_dev->packet_time = (ppm_mode ? packet_time_ppm[datarate] : packet_time[datarate]);
// Find the first N channels that meet the min/max criteria out of the random channel list.
uint8_t num_found = 0;
for (uint16_t i = 0; (i < RFM22B_NUM_CHANNELS) && (num_found < num_channels[datarate]); ++i) {
uint8_t idx = (i + chan_set) % RFM22B_NUM_CHANNELS;
uint8_t chan = channel_list[idx];
if ((chan >= min_chan) && (chan <= max_chan)) {
rfm22b_dev->channels[num_found++] = chan;
}
}
rfm22b_dev->num_channels = num_found;
// Calculate the maximum packet length from the datarate.
float bytes_per_period = (float)data_rate[datarate] * (float)(rfm22b_dev->packet_time - 2) / 9000;
rfm22b_dev->max_packet_len = bytes_per_period - TX_PREAMBLE_NIBBLES / 2 - SYNC_BYTES - HEADER_BYTES - LENGTH_BYTES;
if (rfm22b_dev->max_packet_len > RFM22B_MAX_PACKET_LEN) {
rfm22b_dev->max_packet_len = RFM22B_MAX_PACKET_LEN;
}
}
/**
* Set a modem to be a coordinator or not.
*
* @param[in] rfm22b_id The RFM22B device index.
* @param[in] coordinator If true, this modem will be configured as a coordinator.
*/
extern void PIOS_RFM22B_SetCoordinator(uint32_t rfm22b_id, bool coordinator)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (PIOS_RFM22B_Validate(rfm22b_dev)) {
rfm22b_dev->coordinator = coordinator;
}
}
/**
* Sets the device coordinator ID.
*
* @param[in] rfm22b_id The RFM22B device index.
* @param[in] coord_id The coordinator ID.
*/
void PIOS_RFM22B_SetCoordinatorID(uint32_t rfm22b_id, uint32_t coord_id)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (PIOS_RFM22B_Validate(rfm22b_dev)) {
rfm22b_dev->coordinatorID = coord_id;
}
}
/**
* Returns the device statistics RFM22B device.
*
* @param[in] rfm22b_id The RFM22B device index.
* @param[out] stats The stats are returned in this structure
*/
void PIOS_RFM22B_GetStats(uint32_t rfm22b_id, struct rfm22b_stats *stats)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (!PIOS_RFM22B_Validate(rfm22b_dev)) {
return;
}
// Calculate the current link quality
rfm22_calculateLinkQuality(rfm22b_dev);
// Return the stats.
*stats = rfm22b_dev->stats;
}
/**
* Get the stats of the oter radio devices that are in range.
*
* @param[out] device_ids A pointer to the array to store the device IDs.
* @param[out] RSSIs A pointer to the array to store the RSSI values in.
* @param[in] mx_pairs The length of the pdevice_ids and RSSIs arrays.
* @return The number of pair stats returned.
*/
uint8_t PIOS_RFM2B_GetPairStats(uint32_t rfm22b_id, uint32_t *device_ids, int8_t *RSSIs, uint8_t max_pairs)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (!PIOS_RFM22B_Validate(rfm22b_dev)) {
return 0;
}
uint8_t mp = (max_pairs >= OPLINKSTATUS_PAIRIDS_NUMELEM) ? max_pairs : OPLINKSTATUS_PAIRIDS_NUMELEM;
for (uint8_t i = 0; i < mp; ++i) {
device_ids[i] = rfm22b_dev->pair_stats[i].pairID;
RSSIs[i] = rfm22b_dev->pair_stats[i].rssi;
}
return mp;
}
/**
* Check the radio device for a valid connection
*
* @param[in] rfm22b_id The rfm22b device.
* @return true if there is a valid connection to paired radio, false otherwise.
*/
bool PIOS_RFM22B_LinkStatus(uint32_t rfm22b_id)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (!PIOS_RFM22B_Validate(rfm22b_dev)) {
return false;
}
return rfm22b_dev->stats.link_quality > RFM22B_LINK_QUALITY_THRESHOLD;
}
/**
* Put the RFM22B device into receive mode.
*
* @param[in] rfm22b_id The rfm22b device.
* @param[in] p The packet to receive into.
* @return true if Rx mode was entered sucessfully.
*/
bool PIOS_RFM22B_ReceivePacket(uint32_t rfm22b_id, uint8_t *p)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (!PIOS_RFM22B_Validate(rfm22b_dev)) {
return false;
}
rfm22b_dev->rx_packet_handle = p;
// Claim the SPI bus.
rfm22_claimBus(rfm22b_dev);
// disable interrupts
rfm22_write(rfm22b_dev, RFM22_interrupt_enable1, 0x00);
rfm22_write(rfm22b_dev, RFM22_interrupt_enable2, 0x00);
// Switch to TUNE mode
rfm22_write(rfm22b_dev, RFM22_op_and_func_ctrl1, RFM22_opfc1_pllon);
#ifdef PIOS_RFM22B_DEBUG_ON_TELEM
D2_LED_OFF;
#endif // PIOS_RFM22B_DEBUG_ON_TELEM
RX_LED_OFF;
TX_LED_OFF;
// empty the rx buffer
rfm22b_dev->rx_buffer_wr = 0;
// Clear the TX buffer.
rfm22b_dev->tx_data_rd = rfm22b_dev->tx_data_wr = 0;
// clear FIFOs
rfm22_write(rfm22b_dev, RFM22_op_and_func_ctrl2, RFM22_opfc2_ffclrrx | RFM22_opfc2_ffclrtx);
rfm22_write(rfm22b_dev, RFM22_op_and_func_ctrl2, 0x00);
// enable RX interrupts
rfm22_write(rfm22b_dev, RFM22_interrupt_enable1, RFM22_ie1_encrcerror | RFM22_ie1_enpkvalid |
RFM22_ie1_enrxffafull | RFM22_ie1_enfferr);
rfm22_write(rfm22b_dev, RFM22_interrupt_enable2, RFM22_ie2_enpreainval | RFM22_ie2_enpreaval |
RFM22_ie2_enswdet);
// enable the receiver
rfm22_write(rfm22b_dev, RFM22_op_and_func_ctrl1, RFM22_opfc1_pllon | RFM22_opfc1_rxon);
// Release the SPI bus.
rfm22_releaseBus(rfm22b_dev);
// Indicate that we're in RX wait mode.
rfm22b_dev->rfm22b_state = RFM22B_STATE_RX_WAIT;
return true;
}
/**
* Transmit a packet via the RFM22B device.
*
* @param[in] rfm22b_id The rfm22b device.
* @param[in] p The packet to transmit.
* @return true if there if the packet was queued for transmission.
*/
bool PIOS_RFM22B_TransmitPacket(uint32_t rfm22b_id, uint8_t *p, uint8_t len)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (!PIOS_RFM22B_Validate(rfm22b_dev)) {
return false;
}
rfm22b_dev->tx_packet_handle = p;
rfm22b_dev->stats.tx_byte_count += len;
rfm22b_dev->packet_start_ticks = xTaskGetTickCount();
if (rfm22b_dev->packet_start_ticks == 0) {
rfm22b_dev->packet_start_ticks = 1;
}
// Claim the SPI bus.
rfm22_claimBus(rfm22b_dev);
// Disable interrupts
rfm22_write(rfm22b_dev, RFM22_interrupt_enable1, 0x00);
rfm22_write(rfm22b_dev, RFM22_interrupt_enable2, 0x00);
// set the tx power
rfm22_write(rfm22b_dev, RFM22_tx_power, RFM22_tx_pwr_lna_sw | rfm22b_dev->tx_power);
// TUNE mode
rfm22_write(rfm22b_dev, RFM22_op_and_func_ctrl1, RFM22_opfc1_pllon);
// Queue the data up for sending
rfm22b_dev->tx_data_wr = len;
RX_LED_OFF;
// Set the destination address in the transmit header.
uint32_t id = rfm22_destinationID(rfm22b_dev);
rfm22_write(rfm22b_dev, RFM22_transmit_header0, id & 0xff);
rfm22_write(rfm22b_dev, RFM22_transmit_header1, (id >> 8) & 0xff);
rfm22_write(rfm22b_dev, RFM22_transmit_header2, (id >> 16) & 0xff);
rfm22_write(rfm22b_dev, RFM22_transmit_header3, (id >> 24) & 0xff);
// FIFO mode, GFSK modulation
uint8_t fd_bit = rfm22_read(rfm22b_dev, RFM22_modulation_mode_control2) & RFM22_mmc2_fd;
rfm22_write(rfm22b_dev, RFM22_modulation_mode_control2, fd_bit | RFM22_mmc2_dtmod_fifo | RFM22_mmc2_modtyp_gfsk);
// Clear the FIFOs.
rfm22_write(rfm22b_dev, RFM22_op_and_func_ctrl2, RFM22_opfc2_ffclrrx | RFM22_opfc2_ffclrtx);
rfm22_write(rfm22b_dev, RFM22_op_and_func_ctrl2, 0x00);
// Set the total number of data bytes we are going to transmit.
rfm22_write(rfm22b_dev, RFM22_transmit_packet_length, len);
// Add some data to the chips TX FIFO before enabling the transmitter
uint8_t *tx_buffer = rfm22b_dev->tx_packet_handle;
rfm22_assertCs(rfm22b_dev);
PIOS_SPI_TransferByte(rfm22b_dev->spi_id, RFM22_fifo_access | 0x80);
int bytes_to_write = (rfm22b_dev->tx_data_wr - rfm22b_dev->tx_data_rd);
bytes_to_write = (bytes_to_write > FIFO_SIZE) ? FIFO_SIZE : bytes_to_write;
PIOS_SPI_TransferBlock(rfm22b_dev->spi_id, &tx_buffer[rfm22b_dev->tx_data_rd], NULL, bytes_to_write, NULL);
rfm22b_dev->tx_data_rd += bytes_to_write;
rfm22_deassertCs(rfm22b_dev);
// Enable TX interrupts.
rfm22_write(rfm22b_dev, RFM22_interrupt_enable1, RFM22_ie1_enpksent | RFM22_ie1_entxffaem);
// Enable the transmitter.
rfm22_write(rfm22b_dev, RFM22_op_and_func_ctrl1, RFM22_opfc1_pllon | RFM22_opfc1_txon);
// Release the SPI bus.
rfm22_releaseBus(rfm22b_dev);
// We're in Tx mode.
rfm22b_dev->rfm22b_state = RFM22B_STATE_TX_MODE;
TX_LED_ON;
#ifdef PIOS_RFM22B_DEBUG_ON_TELEM
D1_LED_ON;
#endif
return true;
}
/**
* Process a Tx interrupt from the RFM22B device.
*
* @param[in] rfm22b_id The rfm22b device.
* @return PIOS_RFM22B_TX_COMPLETE on completed Tx, or PIOS_RFM22B_INT_SUCCESS/PIOS_RFM22B_INT_FAILURE.
*/
pios_rfm22b_int_result PIOS_RFM22B_ProcessTx(uint32_t rfm22b_id)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (!PIOS_RFM22B_Validate(rfm22b_dev)) {
return PIOS_RFM22B_INT_FAILURE;
}
// Read the device status registers
if (!pios_rfm22_readStatus(rfm22b_dev)) {
return PIOS_RFM22B_INT_FAILURE;
}
// TX FIFO almost empty, it needs filling up
if (rfm22b_dev->status_regs.int_status_1.tx_fifo_almost_empty) {
// Add data to the TX FIFO buffer
uint8_t *tx_buffer = rfm22b_dev->tx_packet_handle;
uint16_t max_bytes = FIFO_SIZE - TX_FIFO_LO_WATERMARK - 1;
rfm22_claimBus(rfm22b_dev);
rfm22_assertCs(rfm22b_dev);
PIOS_SPI_TransferByte(rfm22b_dev->spi_id, RFM22_fifo_access | 0x80);
int bytes_to_write = (rfm22b_dev->tx_data_wr - rfm22b_dev->tx_data_rd);
bytes_to_write = (bytes_to_write > max_bytes) ? max_bytes : bytes_to_write;
PIOS_SPI_TransferBlock(rfm22b_dev->spi_id, &tx_buffer[rfm22b_dev->tx_data_rd], NULL, bytes_to_write, NULL);
rfm22b_dev->tx_data_rd += bytes_to_write;
rfm22_deassertCs(rfm22b_dev);
rfm22_releaseBus(rfm22b_dev);
return PIOS_RFM22B_INT_SUCCESS;
} else if (rfm22b_dev->status_regs.int_status_1.packet_sent_interrupt) {
// Transition out of Tx mode.
rfm22b_dev->rfm22b_state = RFM22B_STATE_TRANSITION;
return PIOS_RFM22B_TX_COMPLETE;
}
return 0;
}
/**
* Process a Rx interrupt from the RFM22B device.
*
* @param[in] rfm22b_id The rfm22b device.
* @return PIOS_RFM22B_RX_COMPLETE on completed Rx, or PIOS_RFM22B_INT_SUCCESS/PIOS_RFM22B_INT_FAILURE.
*/
pios_rfm22b_int_result PIOS_RFM22B_ProcessRx(uint32_t rfm22b_id)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (!PIOS_RFM22B_Validate(rfm22b_dev)) {
return PIOS_RFM22B_INT_FAILURE;
}
uint8_t *rx_buffer = rfm22b_dev->rx_packet_handle;
pios_rfm22b_int_result ret = PIOS_RFM22B_INT_SUCCESS;
// Read the device status registers
if (!pios_rfm22_readStatus(rfm22b_dev)) {
rfm22_rxFailure(rfm22b_dev);
return PIOS_RFM22B_INT_FAILURE;
}
// FIFO under/over flow error. Restart RX mode.
if (rfm22b_dev->status_regs.int_status_1.fifo_underoverflow_error ||
rfm22b_dev->status_regs.int_status_1.crc_error) {
rfm22_rxFailure(rfm22b_dev);
return PIOS_RFM22B_INT_FAILURE;
}
// Valid packet received
if (rfm22b_dev->status_regs.int_status_1.valid_packet_received) {
// Claim the SPI bus.
rfm22_claimBus(rfm22b_dev);
// read the total length of the packet data
uint32_t len = rfm22_read(rfm22b_dev, RFM22_received_packet_length);
// The received packet is going to be larger than the receive buffer
if (len > rfm22b_dev->max_packet_len) {
rfm22_releaseBus(rfm22b_dev);
rfm22_rxFailure(rfm22b_dev);
return PIOS_RFM22B_INT_FAILURE;
}
// there must still be data in the RX FIFO we need to get
if (rfm22b_dev->rx_buffer_wr < len) {
int32_t bytes_to_read = len - rfm22b_dev->rx_buffer_wr;
// Fetch the data from the RX FIFO
rfm22_assertCs(rfm22b_dev);
PIOS_SPI_TransferByte(rfm22b_dev->spi_id, RFM22_fifo_access & 0x7F);
rfm22b_dev->rx_buffer_wr += (PIOS_SPI_TransferBlock(rfm22b_dev->spi_id, OUT_FF, (uint8_t *)&rx_buffer[rfm22b_dev->rx_buffer_wr],
bytes_to_read, NULL) == 0) ? bytes_to_read : 0;
rfm22_deassertCs(rfm22b_dev);
}
// Read the packet header (destination ID)
rfm22b_dev->rx_destination_id = rfm22_read(rfm22b_dev, RFM22_received_header0);
rfm22b_dev->rx_destination_id |= (rfm22_read(rfm22b_dev, RFM22_received_header1) << 8);
rfm22b_dev->rx_destination_id |= (rfm22_read(rfm22b_dev, RFM22_received_header2) << 16);
rfm22b_dev->rx_destination_id |= (rfm22_read(rfm22b_dev, RFM22_received_header3) << 24);
// Release the SPI bus.
rfm22_releaseBus(rfm22b_dev);
// Is there a length error?
if (rfm22b_dev->rx_buffer_wr != len) {
rfm22_rxFailure(rfm22b_dev);
return PIOS_RFM22B_INT_FAILURE;
}
// Increment the total byte received count.
rfm22b_dev->stats.rx_byte_count += rfm22b_dev->rx_buffer_wr;
// Update the pair status with this packet.
rfm22_updatePairStatus(rfm22b_dev);
// We're finished with Rx mode
rfm22b_dev->rfm22b_state = RFM22B_STATE_TRANSITION;
ret = PIOS_RFM22B_RX_COMPLETE;
} else if (rfm22b_dev->status_regs.int_status_1.rx_fifo_almost_full) {
// RX FIFO almost full, it needs emptying
// read data from the rf chips FIFO buffer
// Claim the SPI bus.
rfm22_claimBus(rfm22b_dev);
// Read the total length of the packet data
uint16_t len = rfm22_read(rfm22b_dev, RFM22_received_packet_length);
// The received packet is going to be larger than the specified length
if ((rfm22b_dev->rx_buffer_wr + RX_FIFO_HI_WATERMARK) > len) {
rfm22_releaseBus(rfm22b_dev);
rfm22_rxFailure(rfm22b_dev);
return PIOS_RFM22B_INT_FAILURE;
}
// The received packet is going to be larger than the receive buffer
if ((rfm22b_dev->rx_buffer_wr + RX_FIFO_HI_WATERMARK) > rfm22b_dev->max_packet_len) {
rfm22_releaseBus(rfm22b_dev);
rfm22_rxFailure(rfm22b_dev);
return PIOS_RFM22B_INT_FAILURE;
}
// Fetch the data from the RX FIFO
rfm22_assertCs(rfm22b_dev);
PIOS_SPI_TransferByte(rfm22b_dev->spi_id, RFM22_fifo_access & 0x7F);
rfm22b_dev->rx_buffer_wr += (PIOS_SPI_TransferBlock(rfm22b_dev->spi_id, OUT_FF, (uint8_t *)&rx_buffer[rfm22b_dev->rx_buffer_wr],
RX_FIFO_HI_WATERMARK, NULL) == 0) ? RX_FIFO_HI_WATERMARK : 0;
rfm22_deassertCs(rfm22b_dev);
// Release the SPI bus.
rfm22_releaseBus(rfm22b_dev);
// Make sure that we're in RX mode.
rfm22b_dev->rfm22b_state = RFM22B_STATE_RX_MODE;
} else if (rfm22b_dev->status_regs.int_status_2.valid_preamble_detected) {
// Valid preamble detected
RX_LED_ON;
// Sync word detected
#ifdef PIOS_RFM22B_DEBUG_ON_TELEM
D2_LED_ON;
#endif // PIOS_RFM22B_DEBUG_ON_TELEM
rfm22b_dev->packet_start_ticks = xTaskGetTickCount();
if (rfm22b_dev->packet_start_ticks == 0) {
rfm22b_dev->packet_start_ticks = 1;
}
// We detected the preamble, now wait for sync.
rfm22b_dev->rfm22b_state = RFM22B_STATE_RX_WAIT_SYNC;
} else if (rfm22b_dev->status_regs.int_status_2.sync_word_detected) {
// Claim the SPI bus.
rfm22_claimBus(rfm22b_dev);
// read the 10-bit signed afc correction value
// bits 9 to 2
uint16_t afc_correction = (uint16_t)rfm22_read(rfm22b_dev, RFM22_afc_correction_read) << 8;
// bits 1 & 0
afc_correction |= (uint16_t)rfm22_read(rfm22b_dev, RFM22_ook_counter_value1) & 0x00c0;
afc_correction >>= 6;
// convert the afc value to Hz
int32_t afc_corr = (int32_t)(rfm22b_dev->frequency_step_size * afc_correction + 0.5f);
rfm22b_dev->afc_correction_Hz = (afc_corr < -127) ? -127 : ((afc_corr > 127) ? 127 : afc_corr);
// read rx signal strength .. 45 = -100dBm, 205 = -20dBm
uint8_t rssi = rfm22_read(rfm22b_dev, RFM22_rssi);
// convert to dBm
rfm22b_dev->rssi_dBm = (int8_t)(rssi >> 1) - 122;
// Release the SPI bus.
rfm22_releaseBus(rfm22b_dev);
// Indicate that we're in RX mode.
rfm22b_dev->rfm22b_state = RFM22B_STATE_RX_MODE;
} else if ((rfm22b_dev->rfm22b_state == RFM22B_STATE_RX_WAIT_SYNC) && !rfm22b_dev->status_regs.int_status_2.valid_preamble_detected) {
// Waiting for the preamble timed out.
rfm22_rxFailure(rfm22b_dev);
return PIOS_RFM22B_INT_FAILURE;
}
return ret;
}
/**
* Set the PPM packet received callback.
*
* @param[in] rfm22b_dev The RFM22B device ID.
* @param[in] cb The callback function pointer.
*/
void PIOS_RFM22B_SetPPMCallback(uint32_t rfm22b_id, PPMReceivedCallback cb)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (!PIOS_RFM22B_Validate(rfm22b_dev)) {
return;
}
rfm22b_dev->ppm_callback = cb;
}
/**
* Set the PPM values to be transmitted.
*
* @param[in] rfm22b_dev The RFM22B device ID.
* @param[in] channels The PPM channel values.
*/
extern void PIOS_RFM22B_PPMSet(uint32_t rfm22b_id, int16_t *channels)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (!PIOS_RFM22B_Validate(rfm22b_dev)) {
return;
}
for (uint8_t i = 0; i < RFM22B_PPM_NUM_CHANNELS; ++i) {
rfm22b_dev->ppm[i] = channels[i];
}
}
/**
* Fetch the PPM values that have been received.
*
* @param[in] rfm22b_dev The RFM22B device structure pointer.
* @param[out] channels The PPM channel values.
*/
extern void PIOS_RFM22B_PPMGet(uint32_t rfm22b_id, int16_t *channels)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)rfm22b_id;
if (!PIOS_RFM22B_Validate(rfm22b_dev)) {
return;
}
for (uint8_t i = 0; i < RFM22B_PPM_NUM_CHANNELS; ++i) {
channels[i] = rfm22b_dev->ppm[i];
}
}
/**
* Validate that the device structure is valid.
*
* @param[in] rfm22b_dev The RFM22B device structure pointer.
*/
inline bool PIOS_RFM22B_Validate(struct pios_rfm22b_dev *rfm22b_dev)
{
return rfm22b_dev != NULL && rfm22b_dev->magic == PIOS_RFM22B_DEV_MAGIC;
}
/*****************************************************************************
* The Device Control Thread
*****************************************************************************/
/**
* The task that controls the radio state machine.
*
* @param[in] paramters The task parameters.
*/
static void pios_rfm22_task(void *parameters)
{
struct pios_rfm22b_dev *rfm22b_dev = (struct pios_rfm22b_dev *)parameters;
if (!PIOS_RFM22B_Validate(rfm22b_dev)) {
return;
}
portTickType lastEventTicks = xTaskGetTickCount();
while (1) {
#if defined(PIOS_INCLUDE_WDG) && defined(PIOS_WDG_RFM22B)
// Update the watchdog timer
PIOS_WDG_UpdateFlag(PIOS_WDG_RFM22B);
#endif /* PIOS_WDG_RFM22B */
// Wait for a signal indicating an external interrupt or a pending send/receive request.
if (xSemaphoreTake(rfm22b_dev->isrPending, ISR_TIMEOUT / portTICK_RATE_MS) == pdTRUE) {
lastEventTicks = xTaskGetTickCount();
// Process events through the state machine.
enum pios_radio_event event;
while (xQueueReceive(rfm22b_dev->eventQueue, &event, 0) == pdTRUE) {
if ((event == RADIO_EVENT_INT_RECEIVED) &&
((rfm22b_dev->state == RADIO_STATE_UNINITIALIZED) || (rfm22b_dev->state == RADIO_STATE_INITIALIZING))) {
continue;
}
rfm22_process_event(rfm22b_dev, event);
}
} else {
// Has it been too long since the last event?
portTickType curTicks = xTaskGetTickCount();
if (pios_rfm22_time_difference_ms(lastEventTicks, curTicks) > PIOS_RFM22B_SUPERVISOR_TIMEOUT) {
// Clear the event queue.
enum pios_radio_event event;
while (xQueueReceive(rfm22b_dev->eventQueue, &event, 0) == pdTRUE) {
// Do nothing;
}
lastEventTicks = xTaskGetTickCount();
// Transsition through an error event.
rfm22_process_event(rfm22b_dev, RADIO_EVENT_ERROR);
}
}
// Change channels if necessary.
if (rfm22_changeChannel(rfm22b_dev)) {
rfm22_process_event(rfm22b_dev, RADIO_EVENT_RX_MODE);
}
portTickType curTicks = xTaskGetTickCount();
// Have we been sending / receiving this packet too long?
if ((rfm22b_dev->packet_start_ticks > 0) &&
(pios_rfm22_time_difference_ms(rfm22b_dev->packet_start_ticks, curTicks) > (rfm22b_dev->packet_time * 3))) {
rfm22_process_event(rfm22b_dev, RADIO_EVENT_TIMEOUT);
}
// Start transmitting a packet if it's time.
bool time_to_send = rfm22_timeToSend(rfm22b_dev);
#ifdef PIOS_RFM22B_DEBUG_ON_TELEM
if (time_to_send) {
D4_LED_ON;
} else {
D4_LED_OFF;
}
#endif
if (time_to_send && PIOS_RFM22B_InRxWait((uint32_t)rfm22b_dev)) {
rfm22_process_event(rfm22b_dev, RADIO_EVENT_TX_START);
}
}
}
/*****************************************************************************
* The State Machine Functions
*****************************************************************************/
/**
* Inject an event into the RFM22B state machine.
*
* @param[in] rfm22b_dev The device structure
* @param[in] event The event to inject
* @param[in] inISR Is this being called from an interrrup service routine?
*/
static void pios_rfm22_inject_event(struct pios_rfm22b_dev *rfm22b_dev, enum pios_radio_event event, bool inISR)
{
if (inISR) {
// Store the event.
portBASE_TYPE pxHigherPriorityTaskWoken1;
if (xQueueSendFromISR(rfm22b_dev->eventQueue, &event, &pxHigherPriorityTaskWoken1) != pdTRUE) {
return;
}
// Signal the semaphore to wake up the handler thread.
portBASE_TYPE pxHigherPriorityTaskWoken2;
if (xSemaphoreGiveFromISR(rfm22b_dev->isrPending, &pxHigherPriorityTaskWoken2) != pdTRUE) {
// Something went fairly seriously wrong
rfm22b_dev->errors++;
}
portEND_SWITCHING_ISR((pxHigherPriorityTaskWoken1 == pdTRUE) || (pxHigherPriorityTaskWoken2 == pdTRUE));
} else {
// Store the event.
if (xQueueSend(rfm22b_dev->eventQueue, &event, portMAX_DELAY) != pdTRUE) {
return;
}
// Signal the semaphore to wake up the handler thread.
if (xSemaphoreGive(rfm22b_dev->isrPending) != pdTRUE) {
// Something went fairly seriously wrong
rfm22b_dev->errors++;
}
}
}
/**
* Process the next state transition from the given event.
*
* @param[in] rfm22b_dev The device structure
* @param[in] event The event to process
* @return enum pios_radio_event The next event to inject
*/
static enum pios_radio_event rfm22_process_state_transition(struct pios_rfm22b_dev *rfm22b_dev, enum pios_radio_event event)
{
// No event
if (event >= RADIO_EVENT_NUM_EVENTS) {
return RADIO_EVENT_NUM_EVENTS;
}
// Don't transition if there is no transition defined
enum pios_radio_state next_state = rfm22b_transitions[rfm22b_dev->state].next_state[event];
if (!next_state) {
return RADIO_EVENT_NUM_EVENTS;
}
/*
* Move to the next state
*
* This is done prior to calling the new state's entry function to
* guarantee that the entry function never depends on the previous
* state. This way, it cannot ever know what the previous state was.
*/
rfm22b_dev->state = next_state;
/* Call the entry function (if any) for the next state. */
if (rfm22b_transitions[rfm22b_dev->state].entry_fn) {
return rfm22b_transitions[rfm22b_dev->state].entry_fn(rfm22b_dev);
}
return RADIO_EVENT_NUM_EVENTS;
}
/**
* Process the given event through the state transition table.
* This could cause a series of events and transitions to take place.
*
* @param[in] rfm22b_dev The device structure
* @param[in] event The event to process
*/
static void rfm22_process_event(struct pios_rfm22b_dev *rfm22b_dev, enum pios_radio_event event)
{
// Process all state transitions.
while (event != RADIO_EVENT_NUM_EVENTS) {
event = rfm22_process_state_transition(rfm22b_dev, event);
}
}
/*****************************************************************************
* The Device Initialization / Configuration Functions
*****************************************************************************/
/**
* Initialize (or re-initialize) the RFM22B radio device.
*
* @param[in] rfm22b_dev The device structure
* @return enum pios_radio_event The next event to inject
*/
static enum pios_radio_event rfm22_init(struct pios_rfm22b_dev *rfm22b_dev)
{
// Initialize the register values.
rfm22b_dev->status_regs.int_status_1.raw = 0;
rfm22b_dev->status_regs.int_status_2.raw = 0;
rfm22b_dev->status_regs.device_status.raw = 0;
rfm22b_dev->status_regs.ezmac_status.raw = 0;
// Clean the LEDs
rfm22_clearLEDs();
// Initialize the detected device statistics.
for (uint8_t i = 0; i < OPLINKSTATUS_PAIRIDS_NUMELEM; ++i) {
rfm22b_dev->pair_stats[i].pairID = 0;
rfm22b_dev->pair_stats[i].rssi = -127;
rfm22b_dev->pair_stats[i].afc_correction = 0;
rfm22b_dev->pair_stats[i].lastContact = 0;
}
// Initlize the link stats.
for (uint8_t i = 0; i < RFM22B_RX_PACKET_STATS_LEN; ++i) {
rfm22b_dev->rx_packet_stats[i] = 0;
}
// Initialize the state
rfm22b_dev->stats.link_state = OPLINKSTATUS_LINKSTATE_ENABLED;
// Initialize the packets.
rfm22b_dev->rx_packet_len = 0;
rfm22b_dev->rx_destination_id = 0;
rfm22b_dev->tx_packet_handle = NULL;
// Initialize the devide state
rfm22b_dev->rx_buffer_wr = 0;
rfm22b_dev->tx_data_rd = rfm22b_dev->tx_data_wr = 0;
rfm22b_dev->channel = 0;
rfm22b_dev->channel_index = 0;
rfm22b_dev->afc_correction_Hz = 0;
rfm22b_dev->packet_start_ticks = 0;
rfm22b_dev->tx_complete_ticks = 0;
rfm22b_dev->rfm22b_state = RFM22B_STATE_INITIALIZING;
rfm22b_dev->connected_timeout = 0;
// software reset the RF chip .. following procedure according to Si4x3x Errata (rev. B)
rfm22_write_claim(rfm22b_dev, RFM22_op_and_func_ctrl1, RFM22_opfc1_swres);
for (uint8_t i = 0; i < 50; ++i) {
// read the status registers
pios_rfm22_readStatus(rfm22b_dev);
// Is the chip ready?
if (rfm22b_dev->status_regs.int_status_2.chip_ready) {
break;
}
// Wait 1ms if not.
PIOS_DELAY_WaitmS(1);
}
// ****************
// read status - clears interrupt
pios_rfm22_readStatus(rfm22b_dev);
// Claim the SPI bus.
rfm22_claimBus(rfm22b_dev);
// disable all interrupts
rfm22_write(rfm22b_dev, RFM22_interrupt_enable1, 0x00);
rfm22_write(rfm22b_dev, RFM22_interrupt_enable2, 0x00);
// read the RF chip ID bytes
// read the device type
uint8_t device_type = rfm22_read(rfm22b_dev, RFM22_DEVICE_TYPE) & RFM22_DT_MASK;
// read the device version
uint8_t device_version = rfm22_read(rfm22b_dev, RFM22_DEVICE_VERSION) & RFM22_DV_MASK;
#if defined(RFM22_DEBUG)
DEBUG_PRINTF(2, "rf device type: %d\n\r", device_type);
DEBUG_PRINTF(2, "rf device version: %d\n\r", device_version);
#endif
if (device_type != 0x08) {
#if defined(RFM22_DEBUG)
DEBUG_PRINTF(2, "rf device type: INCORRECT - should be 0x08\n\r");
#endif
// incorrect RF module type
return RADIO_EVENT_FATAL_ERROR;
}
if (device_version != RFM22_DEVICE_VERSION_B1) {
#if defined(RFM22_DEBUG)
DEBUG_PRINTF(2, "rf device version: INCORRECT\n\r");
#endif
// incorrect RF module version
return RADIO_EVENT_FATAL_ERROR;
}
// calibrate our RF module to be exactly on frequency .. different for every module
rfm22_write(rfm22b_dev, RFM22_xtal_osc_load_cap, OSC_LOAD_CAP);
// disable Low Duty Cycle Mode
rfm22_write(rfm22b_dev, RFM22_op_and_func_ctrl2, 0x00);
// 1MHz clock output
rfm22_write(rfm22b_dev, RFM22_cpu_output_clk, RFM22_coc_1MHz);
// READY mode
rfm22_write(rfm22b_dev, RFM22_op_and_func_ctrl1, RFM22_opfc1_xton);
// choose the 3 GPIO pin functions
// GPIO port use default value
rfm22_write(rfm22b_dev, RFM22_io_port_config, RFM22_io_port_default);
if (rfm22b_dev->cfg.gpio_direction == GPIO0_TX_GPIO1_RX) {
// GPIO0 = TX State (to control RF Switch)
rfm22_write(rfm22b_dev, RFM22_gpio0_config, RFM22_gpio0_config_drv3 | RFM22_gpio0_config_txstate);
// GPIO1 = RX State (to control RF Switch)
rfm22_write(rfm22b_dev, RFM22_gpio1_config, RFM22_gpio1_config_drv3 | RFM22_gpio1_config_rxstate);
} else {
// GPIO0 = TX State (to control RF Switch)
rfm22_write(rfm22b_dev, RFM22_gpio0_config, RFM22_gpio0_config_drv3 | RFM22_gpio0_config_rxstate);
// GPIO1 = RX State (to control RF Switch)
rfm22_write(rfm22b_dev, RFM22_gpio1_config, RFM22_gpio1_config_drv3 | RFM22_gpio1_config_txstate);
}
// GPIO2 = Clear Channel Assessment
rfm22_write(rfm22b_dev, RFM22_gpio2_config, RFM22_gpio2_config_drv3 | RFM22_gpio2_config_cca);
// FIFO mode, GFSK modulation
uint8_t fd_bit = rfm22_read(rfm22b_dev, RFM22_modulation_mode_control2) & RFM22_mmc2_fd;
rfm22_write(rfm22b_dev, RFM22_modulation_mode_control2, RFM22_mmc2_trclk_clk_none | RFM22_mmc2_dtmod_fifo | fd_bit | RFM22_mmc2_modtyp_gfsk);
// setup to read the internal temperature sensor
// ADC used to sample the temperature sensor
uint8_t adc_config = RFM22_ac_adcsel_temp_sensor | RFM22_ac_adcref_bg;
rfm22_write(rfm22b_dev, RFM22_adc_config, adc_config);
// adc offset
rfm22_write(rfm22b_dev, RFM22_adc_sensor_amp_offset, 0);
// temp sensor calibration .. <20>40C to +64C 0.5C resolution
rfm22_write(rfm22b_dev, RFM22_temp_sensor_calib, RFM22_tsc_tsrange0 | RFM22_tsc_entsoffs);
// temp sensor offset
rfm22_write(rfm22b_dev, RFM22_temp_value_offset, 0);
// start an ADC conversion
rfm22_write(rfm22b_dev, RFM22_adc_config, adc_config | RFM22_ac_adcstartbusy);
// set the RSSI threshold interrupt to about -90dBm
rfm22_write(rfm22b_dev, RFM22_rssi_threshold_clear_chan_indicator, (-90 + 122) * 2);
// enable the internal Tx & Rx packet handlers (without CRC)
rfm22_write(rfm22b_dev, RFM22_data_access_control, RFM22_dac_enpacrx | RFM22_dac_enpactx);
// x-nibbles tx preamble
rfm22_write(rfm22b_dev, RFM22_preamble_length, TX_PREAMBLE_NIBBLES);
// x-nibbles rx preamble detection
rfm22_write(rfm22b_dev, RFM22_preamble_detection_ctrl1, RX_PREAMBLE_NIBBLES << 3);
// header control - using a 4 by header with broadcast of 0xffffffff
rfm22_write(rfm22b_dev, RFM22_header_control1,
RFM22_header_cntl1_bcen_0 |
RFM22_header_cntl1_bcen_1 |
RFM22_header_cntl1_bcen_2 |
RFM22_header_cntl1_bcen_3 |
RFM22_header_cntl1_hdch_0 |
RFM22_header_cntl1_hdch_1 |
RFM22_header_cntl1_hdch_2 |
RFM22_header_cntl1_hdch_3);
// Check all bit of all bytes of the header, unless we're an unbound modem.
uint8_t header_mask = (rfm22_destinationID(rfm22b_dev) == 0xffffffff) ? 0 : 0xff;
rfm22_write(rfm22b_dev, RFM22_header_enable0, header_mask);
rfm22_write(rfm22b_dev, RFM22_header_enable1, header_mask);
rfm22_write(rfm22b_dev, RFM22_header_enable2, header_mask);
rfm22_write(rfm22b_dev, RFM22_header_enable3, header_mask);
// The destination ID and receive ID should be the same.
uint32_t id = rfm22_destinationID(rfm22b_dev);
rfm22_write(rfm22b_dev, RFM22_check_header0, id & 0xff);
rfm22_write(rfm22b_dev, RFM22_check_header1, (id >> 8) & 0xff);
rfm22_write(rfm22b_dev, RFM22_check_header2, (id >> 16) & 0xff);
rfm22_write(rfm22b_dev, RFM22_check_header3, (id >> 24) & 0xff);
// 4 header bytes, synchronization word length 3, 2, 1 & 0 used, packet length included in header.
rfm22_write(rfm22b_dev, RFM22_header_control2,
RFM22_header_cntl2_hdlen_3210 |
RFM22_header_cntl2_synclen_3210 |
((TX_PREAMBLE_NIBBLES >> 8) & 0x01));
// sync word
rfm22_write(rfm22b_dev, RFM22_sync_word3, SYNC_BYTE_1);
rfm22_write(rfm22b_dev, RFM22_sync_word2, SYNC_BYTE_2);
rfm22_write(rfm22b_dev, RFM22_sync_word1, SYNC_BYTE_3);
rfm22_write(rfm22b_dev, RFM22_sync_word0, SYNC_BYTE_4);
// TX FIFO Almost Full Threshold (0 - 63)
rfm22_write(rfm22b_dev, RFM22_tx_fifo_control1, TX_FIFO_HI_WATERMARK);
// TX FIFO Almost Empty Threshold (0 - 63)
rfm22_write(rfm22b_dev, RFM22_tx_fifo_control2, TX_FIFO_LO_WATERMARK);
// RX FIFO Almost Full Threshold (0 - 63)
rfm22_write(rfm22b_dev, RFM22_rx_fifo_control, RX_FIFO_HI_WATERMARK);
// Set the frequency calibration
rfm22_write(rfm22b_dev, RFM22_xtal_osc_load_cap, rfm22b_dev->cfg.RFXtalCap);
// Release the bus
rfm22_releaseBus(rfm22b_dev);
// Initialize the frequency and datarate to te default.
rfm22_setNominalCarrierFrequency(rfm22b_dev, 0);
pios_rfm22_setDatarate(rfm22b_dev);
return RADIO_EVENT_INITIALIZED;
}
/**
* Set the air datarate for the RFM22B device.
*
* Carson's rule:
* The signal bandwidth is about 2(Delta-f + fm) ..
*
* Delta-f = frequency deviation
* fm = maximum frequency of the signal
*
* @param[in] rfm33b_dev The device structure pointer.
* @param[in] datarate The air datarate.
* @param[in] data_whitening Is data whitening desired?
*/
static void pios_rfm22_setDatarate(struct pios_rfm22b_dev *rfm22b_dev)
{
enum rfm22b_datarate datarate = rfm22b_dev->datarate;
bool data_whitening = true;
// Claim the SPI bus.
rfm22_claimBus(rfm22b_dev);
// rfm22_if_filter_bandwidth
rfm22_write(rfm22b_dev, 0x1C, reg_1C[datarate]);
// rfm22_afc_loop_gearshift_override
rfm22_write(rfm22b_dev, 0x1D, reg_1D[datarate]);
// RFM22_afc_timing_control
rfm22_write(rfm22b_dev, 0x1E, reg_1E[datarate]);
// RFM22_clk_recovery_gearshift_override
rfm22_write(rfm22b_dev, 0x1F, reg_1F[datarate]);
// rfm22_clk_recovery_oversampling_ratio
rfm22_write(rfm22b_dev, 0x20, reg_20[datarate]);
// rfm22_clk_recovery_offset2
rfm22_write(rfm22b_dev, 0x21, reg_21[datarate]);
// rfm22_clk_recovery_offset1
rfm22_write(rfm22b_dev, 0x22, reg_22[datarate]);
// rfm22_clk_recovery_offset0
rfm22_write(rfm22b_dev, 0x23, reg_23[datarate]);
// rfm22_clk_recovery_timing_loop_gain1
rfm22_write(rfm22b_dev, 0x24, reg_24[datarate]);
// rfm22_clk_recovery_timing_loop_gain0
rfm22_write(rfm22b_dev, 0x25, reg_25[datarate]);
// rfm22_agc_override1
rfm22_write(rfm22b_dev, RFM22_agc_override1, reg_69[datarate]);
// rfm22_afc_limiter
rfm22_write(rfm22b_dev, 0x2A, reg_2A[datarate]);
// rfm22_tx_data_rate1
rfm22_write(rfm22b_dev, 0x6E, reg_6E[datarate]);
// rfm22_tx_data_rate0
rfm22_write(rfm22b_dev, 0x6F, reg_6F[datarate]);
if (!data_whitening) {
// rfm22_modulation_mode_control1
rfm22_write(rfm22b_dev, 0x70, reg_70[datarate] & ~RFM22_mmc1_enwhite);
} else {
// rfm22_modulation_mode_control1
rfm22_write(rfm22b_dev, 0x70, reg_70[datarate] | RFM22_mmc1_enwhite);
}
// rfm22_modulation_mode_control2
rfm22_write(rfm22b_dev, 0x71, reg_71[datarate]);
// rfm22_frequency_deviation
rfm22_write(rfm22b_dev, 0x72, reg_72[datarate]);
// rfm22_cpcuu
rfm22_write(rfm22b_dev, 0x58, reg_58[datarate]);
rfm22_write(rfm22b_dev, RFM22_ook_counter_value1, 0x00);
rfm22_write(rfm22b_dev, RFM22_ook_counter_value2, 0x00);
// Release the bus
rfm22_releaseBus(rfm22b_dev);
}
/**
* Set the nominal carrier frequency, channel step size, and initial channel
*
* @param[in] rfm33b_dev The device structure pointer.
* @param[in] init_chan The initial channel to tune to.
*/
static void rfm22_setNominalCarrierFrequency(struct pios_rfm22b_dev *rfm22b_dev, uint8_t init_chan)
{
// Set the frequency channels to start at 430MHz
uint32_t frequency_hz = RFM22B_NOMINAL_CARRIER_FREQUENCY;
// The step size is 10MHz / 250 channels = 40khz, and the step size is specified in 10khz increments.
uint8_t freq_hop_step_size = 4;
// holds the hbsel (1 or 2)
uint8_t hbsel;
if (frequency_hz < 480000000) {
hbsel = 0;
} else {
hbsel = 1;
}
float freq_mhz = (float)(frequency_hz) / 1000000.0f;
float xtal_freq_khz = 30000.0f;
float sfreq = freq_mhz / (10.0f * (xtal_freq_khz / 30000.0f) * (1 + hbsel));
uint32_t fb = (uint32_t)sfreq - 24 + (64 + 32 * hbsel);
uint32_t fc = (uint32_t)((sfreq - (uint32_t)sfreq) * 64000.0f);
uint8_t fch = (fc >> 8) & 0xff;
uint8_t fcl = fc & 0xff;
// Claim the SPI bus.
rfm22_claimBus(rfm22b_dev);
// Setthe frequency hopping step size.
rfm22_write(rfm22b_dev, RFM22_frequency_hopping_step_size, freq_hop_step_size);
// frequency hopping channel (0-255)
rfm22b_dev->frequency_step_size = 156.25f * hbsel;
// frequency hopping channel (0-255)
rfm22b_dev->channel = init_chan;
rfm22_write(rfm22b_dev, RFM22_frequency_hopping_channel_select, init_chan);
// no frequency offset
rfm22_write(rfm22b_dev, RFM22_frequency_offset1, 0);
rfm22_write(rfm22b_dev, RFM22_frequency_offset2, 0);
// set the carrier frequency
rfm22_write(rfm22b_dev, RFM22_frequency_band_select, fb & 0xff);
rfm22_write(rfm22b_dev, RFM22_nominal_carrier_frequency1, fch);
rfm22_write(rfm22b_dev, RFM22_nominal_carrier_frequency0, fcl);
// Release the bus
rfm22_releaseBus(rfm22b_dev);
}
/**
* Set the frequency hopping channel.
*
* @param[in] rfm33b_dev The device structure pointer.
*/
static bool rfm22_setFreqHopChannel(struct pios_rfm22b_dev *rfm22b_dev, uint8_t channel)
{
// set the frequency hopping channel
if (rfm22b_dev->channel == channel) {
return false;
}
#ifdef PIOS_RFM22B_DEBUG_ON_TELEM
D3_LED_TOGGLE;
#endif // PIOS_RFM22B_DEBUG_ON_TELEM
rfm22b_dev->channel = channel;
rfm22_write_claim(rfm22b_dev, RFM22_frequency_hopping_channel_select, channel);
return true;
}
/**
* Read the RFM22B interrupt and device status registers
*
* @param[in] rfm22b_dev The device structure
*/
static bool pios_rfm22_readStatus(struct pios_rfm22b_dev *rfm22b_dev)
{
// 1. Read the interrupt statuses with burst read
rfm22_claimBus(rfm22b_dev); // Set RC and the semaphore
uint8_t write_buf[3] = { RFM22_interrupt_status1 &0x7f, 0xFF, 0xFF };
uint8_t read_buf[3];
rfm22_assertCs(rfm22b_dev);
PIOS_SPI_TransferBlock(rfm22b_dev->spi_id, write_buf, read_buf, sizeof(write_buf), NULL);
rfm22_deassertCs(rfm22b_dev);
rfm22b_dev->status_regs.int_status_1.raw = read_buf[1];
rfm22b_dev->status_regs.int_status_2.raw = read_buf[2];
// Device status
rfm22b_dev->status_regs.device_status.raw = rfm22_read(rfm22b_dev, RFM22_device_status);
// EzMAC status
rfm22b_dev->status_regs.ezmac_status.raw = rfm22_read(rfm22b_dev, RFM22_ezmac_status);
// Release the bus
rfm22_releaseBus(rfm22b_dev);
// the RF module has gone and done a reset - we need to re-initialize the rf module
if (rfm22b_dev->status_regs.int_status_2.poweron_reset) {
return false;
}
return true;
}
/**
* Recover from a failure in receiving a packet.
*
* @param[in] rfm22b_dev The device structure
* @return enum pios_radio_event The next event to inject
*/
static void rfm22_rxFailure(struct pios_rfm22b_dev *rfm22b_dev)
{
rfm22b_dev->stats.rx_failure++;
rfm22b_dev->rx_buffer_wr = 0;
rfm22b_dev->packet_start_ticks = 0;
rfm22b_dev->rfm22b_state = RFM22B_STATE_TRANSITION;
}
/*****************************************************************************
* Radio Transmit and Receive functions.
*****************************************************************************/
/**
* Start a transmit if possible
*
* @param[in] radio_dev The device structure
* @return enum pios_radio_event The next event to inject
*/
static enum pios_radio_event radio_txStart(struct pios_rfm22b_dev *radio_dev)
{
uint8_t *p = radio_dev->tx_packet;
uint8_t len = 0;
uint8_t max_data_len = radio_dev->max_packet_len - (radio_dev->ppm_only_mode ? 0 : RS_ECC_NPARITY);
// Don't send if it's not our turn, or if we're receiving a packet.
if (!rfm22_timeToSend(radio_dev) || !PIOS_RFM22B_InRxWait((uint32_t)radio_dev)) {
return RADIO_EVENT_RX_MODE;
}
// Don't send anything if we're bound to a coordinator and not yet connected.
if (!rfm22_isCoordinator(radio_dev) && !rfm22_isConnected(radio_dev)) {
return RADIO_EVENT_RX_MODE;
}
// Should we append PPM data to the packet?
if (radio_dev->ppm_send_mode) {
len = RFM22B_PPM_NUM_CHANNELS + (radio_dev->ppm_only_mode ? 2 : 1);
// Ensure we can fit the PPM data in the packet.
if (max_data_len < len) {
return RADIO_EVENT_RX_MODE;
}
// The first byte is a bitmask of valid channels.
p[0] = 0;
// Read the PPM input.
for (uint8_t i = 0; i < RFM22B_PPM_NUM_CHANNELS; ++i) {
int32_t val = radio_dev->ppm[i];
if ((val == PIOS_RCVR_INVALID) || (val == PIOS_RCVR_TIMEOUT)) {
p[i + 1] = 0;
} else {
p[0] |= 1 << i;
p[i + 1] = (val < 1000) ? 0 : ((val >= 1900) ? 255 : (uint8_t)(256 * (val - 1000) / 900));
}
}
// The last byte is a CRC.
if (radio_dev->ppm_only_mode) {
uint8_t crc = 0;
for (uint8_t i = 0; i < RFM22B_PPM_NUM_CHANNELS + 1; ++i) {
crc = PIOS_CRC_updateByte(crc, p[i]);
}
p[RFM22B_PPM_NUM_CHANNELS + 1] = crc;
}
}
// Append data from the com interface if applicable.
if (!radio_dev->ppm_only_mode && radio_dev->tx_out_cb) {
// Try to get some data to send
bool need_yield = false;
len += (radio_dev->tx_out_cb)(radio_dev->tx_out_context, p + len, max_data_len - len, NULL, &need_yield);
}
// Always send a packet if this modem is a coordinator.
if ((len == 0) && !rfm22_isCoordinator(radio_dev)) {
return RADIO_EVENT_RX_MODE;
}
// Increment the packet sequence number.
radio_dev->stats.tx_seq++;
// Add the error correcting code.
if (!radio_dev->ppm_only_mode) {
if (len != 0) {
encode_data((unsigned char *)p, len, (unsigned char *)p);
}
len += RS_ECC_NPARITY;
}
// Transmit the packet.
PIOS_RFM22B_TransmitPacket((uint32_t)radio_dev, p, len);
return RADIO_EVENT_NUM_EVENTS;
}
/**
* Transmit packet data.
*
* @param[in] rfm22b_dev The device structure
* @return enum pios_radio_event The next event to inject
*/
static enum pios_radio_event radio_txData(struct pios_rfm22b_dev *radio_dev)
{
enum pios_radio_event ret_event = RADIO_EVENT_NUM_EVENTS;
pios_rfm22b_int_result res = PIOS_RFM22B_ProcessTx((uint32_t)radio_dev);
// Is the transmition complete
if (res == PIOS_RFM22B_TX_COMPLETE) {
radio_dev->tx_complete_ticks = xTaskGetTickCount();
// Is this an ACK?
ret_event = RADIO_EVENT_RX_MODE;
radio_dev->tx_packet_handle = 0;
radio_dev->tx_data_wr = radio_dev->tx_data_rd = 0;
// Start a new transaction
radio_dev->packet_start_ticks = 0;
#ifdef PIOS_RFM22B_DEBUG_ON_TELEM
D1_LED_OFF;
#endif
}
return ret_event;
}
/**
* Switch the radio into receive mode.
*
* @param[in] rfm22b_dev The device structure
* @return enum pios_radio_event The next event to inject
*/
static enum pios_radio_event radio_setRxMode(struct pios_rfm22b_dev *rfm22b_dev)
{
if (!PIOS_RFM22B_ReceivePacket((uint32_t)rfm22b_dev, rfm22b_dev->rx_packet)) {
return RADIO_EVENT_NUM_EVENTS;
}
rfm22b_dev->packet_start_ticks = 0;
// No event generated
return RADIO_EVENT_NUM_EVENTS;
}
/**
* Complete the receipt of a packet.
*
* @param[in] radio_dev The device structure
* @param[in] p The packet handle of the received packet.
* @param[in] rc_len The number of bytes received.
* @return enum pios_radio_event The next event to inject
*/
static enum pios_radio_event radio_receivePacket(struct pios_rfm22b_dev *radio_dev, uint8_t *p, uint16_t rx_len)
{
bool good_packet = true;
bool corrected_packet = false;
uint8_t data_len = rx_len;
// We don't rsencode ppm only packets.
if (!radio_dev->ppm_only_mode) {
data_len -= RS_ECC_NPARITY;
// Attempt to correct any errors in the packet.
if (data_len > 0) {
decode_data((unsigned char *)p, rx_len);
good_packet = check_syndrome() == 0;
// We have an error. Try to correct it.
if (!good_packet && (correct_errors_erasures((unsigned char *)p, rx_len, 0, 0) != 0)) {
// We corrected it
corrected_packet = true;
}
}
}
// Should we pull PPM data off of the head of the packet?
if ((good_packet || corrected_packet) && radio_dev->ppm_recv_mode) {
uint8_t ppm_len = RFM22B_PPM_NUM_CHANNELS + (radio_dev->ppm_only_mode ? 2 : 1);
// Ensure the packet it long enough
if (data_len < ppm_len) {
good_packet = false;
}
// Verify the CRC if this is a PPM only packet.
if ((good_packet || corrected_packet) && radio_dev->ppm_only_mode) {
uint8_t crc = 0;
for (uint8_t i = 0; i < RFM22B_PPM_NUM_CHANNELS + 1; ++i) {
crc = PIOS_CRC_updateByte(crc, p[i]);
}
if (p[RFM22B_PPM_NUM_CHANNELS + 1] != crc) {
good_packet = false;
corrected_packet = false;
}
}
if (good_packet || corrected_packet) {
for (uint8_t i = 0; i < RFM22B_PPM_NUM_CHANNELS; ++i) {
// Is this a valid channel?
if (p[0] & (1 << i)) {
uint32_t val = p[i + 1];
radio_dev->ppm[i] = (uint16_t)(1000 + val * 900 / 256);
} else {
radio_dev->ppm[i] = PIOS_RCVR_INVALID;
}
}
p += RFM22B_PPM_NUM_CHANNELS + 1;
data_len -= RFM22B_PPM_NUM_CHANNELS + 1;
// Call the PPM received callback if it's available.
if (radio_dev->ppm_callback) {
radio_dev->ppm_callback(radio_dev->ppm);
}
}
}
// Set the packet status
if (good_packet) {
rfm22b_add_rx_status(radio_dev, RADIO_GOOD_RX_PACKET);
} else if (corrected_packet) {
// We corrected the error.
rfm22b_add_rx_status(radio_dev, RADIO_CORRECTED_RX_PACKET);
} else {
// We couldn't correct the error, so drop the packet.
rfm22b_add_rx_status(radio_dev, RADIO_ERROR_RX_PACKET);
}
enum pios_radio_event ret_event = RADIO_EVENT_RX_COMPLETE;
if (good_packet || corrected_packet) {
// Send the data to the com port
bool rx_need_yield;
if (radio_dev->rx_in_cb && (data_len > 0) && !radio_dev->ppm_only_mode) {
(radio_dev->rx_in_cb)(radio_dev->rx_in_context, p, data_len, NULL, &rx_need_yield);
}
/*
* If the packet is valid and destined for us we synchronize the clock.
*/
if (!rfm22_isCoordinator(radio_dev) &&
radio_dev->rx_destination_id == rfm22_destinationID(radio_dev)) {
rfm22_synchronizeClock(radio_dev);
radio_dev->stats.link_state = OPLINKSTATUS_LINKSTATE_CONNECTED;
}
radio_dev->connected_timeout = CONNECTED_LIVE;
} else {
ret_event = RADIO_EVENT_RX_COMPLETE;
}
return ret_event;
}
/**
* Receive the packet data.
*
* @param[in] rfm22b_dev The device structure
* @return enum pios_radio_event The next event to inject
*/
static enum pios_radio_event radio_rxData(struct pios_rfm22b_dev *radio_dev)
{
enum pios_radio_event ret_event = RADIO_EVENT_NUM_EVENTS;
pios_rfm22b_int_result res = PIOS_RFM22B_ProcessRx((uint32_t)radio_dev);
switch (res) {
case PIOS_RFM22B_RX_COMPLETE:
// Receive the packet.
ret_event = radio_receivePacket(radio_dev, radio_dev->rx_packet_handle, radio_dev->rx_buffer_wr);
radio_dev->rx_buffer_wr = 0;
#ifdef PIOS_RFM22B_DEBUG_ON_TELEM
D2_LED_OFF;
#endif
// Start a new transaction
radio_dev->packet_start_ticks = 0;
break;
case PIOS_RFM22B_INT_FAILURE:
ret_event = RADIO_EVENT_RX_MODE;
break;
default:
// do nothing.
break;
}
return ret_event;
}
/*****************************************************************************
* Link Statistics Functions
*****************************************************************************/
/**
* Update the modem pair status.
*
* @param[in] rfm22b_dev The device structure
*/
static void rfm22_updatePairStatus(struct pios_rfm22b_dev *radio_dev)
{
int8_t rssi = radio_dev->rssi_dBm;
int8_t afc = radio_dev->afc_correction_Hz;
uint32_t id = radio_dev->rx_destination_id;
// Have we seen this device recently?
bool found = false;
uint8_t id_idx = 0;
for (; id_idx < OPLINKSTATUS_PAIRIDS_NUMELEM; ++id_idx) {
if (radio_dev->pair_stats[id_idx].pairID == id) {
found = true;
break;
}
}
// If we have seen it, update the RSSI and reset the last contact counter
if (found) {
radio_dev->pair_stats[id_idx].rssi = rssi;
radio_dev->pair_stats[id_idx].afc_correction = afc;
radio_dev->pair_stats[id_idx].lastContact = 0;
} else {
// If we haven't seen it, find a slot to put it in.
uint8_t min_idx = 0;
int8_t min_rssi = radio_dev->pair_stats[0].rssi;
for (id_idx = 1; id_idx < OPLINKSTATUS_PAIRIDS_NUMELEM; ++id_idx) {
if (radio_dev->pair_stats[id_idx].rssi < min_rssi) {
min_rssi = radio_dev->pair_stats[id_idx].rssi;
min_idx = id_idx;
}
}
radio_dev->pair_stats[min_idx].pairID = id;
radio_dev->pair_stats[min_idx].rssi = rssi;
radio_dev->pair_stats[min_idx].afc_correction = afc;
radio_dev->pair_stats[min_idx].lastContact = 0;
}
}
/**
* Calculate the link quality from the packet receipt, tranmittion statistics.
*
* @param[in] rfm22b_dev The device structure
*/
static void rfm22_calculateLinkQuality(struct pios_rfm22b_dev *rfm22b_dev)
{
// Add the RX packet statistics
rfm22b_dev->stats.rx_good = 0;
rfm22b_dev->stats.rx_corrected = 0;
rfm22b_dev->stats.rx_error = 0;
rfm22b_dev->stats.tx_resent = 0;
for (uint8_t i = 0; i < RFM22B_RX_PACKET_STATS_LEN; ++i) {
uint32_t val = rfm22b_dev->rx_packet_stats[i];
for (uint8_t j = 0; j < 16; ++j) {
switch ((val >> (j * 2)) & 0x3) {
case RADIO_GOOD_RX_PACKET:
rfm22b_dev->stats.rx_good++;
break;
case RADIO_CORRECTED_RX_PACKET:
rfm22b_dev->stats.rx_corrected++;
break;
case RADIO_ERROR_RX_PACKET:
rfm22b_dev->stats.rx_error++;
break;
case RADIO_RESENT_TX_PACKET:
rfm22b_dev->stats.tx_resent++;
break;
}
}
}
// Calculate the link quality metric, which is related to the number of good packets in relation to the number of bad packets.
// Note: This assumes that the number of packets sampled for the stats is 64.
// Using this equation, error and resent packets are counted as -2, and corrected packets are counted as -1.
// The range is 0 (all error or resent packets) to 128 (all good packets).
rfm22b_dev->stats.link_quality = 64 + rfm22b_dev->stats.rx_good - rfm22b_dev->stats.rx_error - rfm22b_dev->stats.tx_resent;
}
/**
* Add a status value to the RX packet status array.
*
* @param[in] rfm22b_dev The device structure
* @param[in] status The packet status value
*/
static void rfm22b_add_rx_status(struct pios_rfm22b_dev *rfm22b_dev, enum pios_rfm22b_rx_packet_status status)
{
// Shift the status registers
for (uint8_t i = RFM22B_RX_PACKET_STATS_LEN - 1; i > 0; --i) {
rfm22b_dev->rx_packet_stats[i] = (rfm22b_dev->rx_packet_stats[i] << 2) | (rfm22b_dev->rx_packet_stats[i - 1] >> 30);
}
rfm22b_dev->rx_packet_stats[0] = (rfm22b_dev->rx_packet_stats[0] << 2) | status;
}
/*****************************************************************************
* Connection Handling Functions
*****************************************************************************/
/**
* Are we a coordinator modem?
*
* @param[in] rfm22b_dev The device structure
*/
static bool rfm22_isCoordinator(struct pios_rfm22b_dev *rfm22b_dev)
{
return rfm22b_dev->coordinator;
}
/**
* Returns the destination ID to send packets to.
*
* @param[in] rfm22b_id The RFM22B device index.
* @return The destination ID
*/
uint32_t rfm22_destinationID(struct pios_rfm22b_dev *rfm22b_dev)
{
if (rfm22_isCoordinator(rfm22b_dev)) {
return rfm22b_dev->deviceID;
} else if (rfm22b_dev->coordinatorID) {
return rfm22b_dev->coordinatorID;
} else {
return 0xffffffff;
}
}
/*****************************************************************************
* Frequency Hopping Functions
*****************************************************************************/
/**
* Synchronize the clock after a packet receive from our coordinator on the syncronization channel.
* This function should be called when a packet is received on the synchronization channel.
*
* @param[in] rfm22b_dev The device structure
*/
static void rfm22_synchronizeClock(struct pios_rfm22b_dev *rfm22b_dev)
{
portTickType start_time = rfm22b_dev->packet_start_ticks;
// This packet was transmitted on channel 0, calculate the time delta that will force us to transmit on channel 0 at the time this packet started.
uint16_t frequency_hop_cycle_time = rfm22b_dev->packet_time * rfm22b_dev->num_channels;
uint16_t time_delta = start_time % frequency_hop_cycle_time;
// Calculate the adjustment for the preamble
uint8_t offset = (uint8_t)ceil(35000.0F / data_rate[rfm22b_dev->datarate]);
rfm22b_dev->time_delta = frequency_hop_cycle_time - time_delta + offset +
rfm22b_dev->packet_time * rfm22b_dev->channel_index;
}
/**
* Return the extimated current clock ticks count on the coordinator modem.
* This is the master clock used for all synchronization.
*
* @param[in] rfm22b_dev The device structure
*/
static portTickType rfm22_coordinatorTime(struct pios_rfm22b_dev *rfm22b_dev, portTickType ticks)
{
if (rfm22_isCoordinator(rfm22b_dev)) {
return ticks;
}
return ticks + rfm22b_dev->time_delta;
}
/**
* Return true if this modem is in the send interval, which allows the modem to initiate a transmit.
*
* @param[in] rfm22b_dev The device structure
*/
static bool rfm22_timeToSend(struct pios_rfm22b_dev *rfm22b_dev)
{
portTickType time = rfm22_coordinatorTime(rfm22b_dev, xTaskGetTickCount());
bool is_coordinator = rfm22_isCoordinator(rfm22b_dev);
// If this is a one-way link, only the coordinator can send.
uint8_t packet_period = rfm22b_dev->packet_time;
if (rfm22b_dev->one_way_link) {
if (is_coordinator) {
return ((time - 1) % (packet_period)) == 0;
} else {
return false;
}
}
if (!is_coordinator) {
time += packet_period - 1;
} else {
time -= 1;
}
return (time % (packet_period * 2)) == 0;
}
/**
* Calculate the nth channel index.
*
* @param[in] rfm22b_dev The device structure
* @param[in] index The channel index to calculate
*/
static uint8_t rfm22_calcChannel(struct pios_rfm22b_dev *rfm22b_dev, uint8_t index)
{
// Make sure we don't index outside of the range.
uint8_t idx = index % rfm22b_dev->num_channels;
// Are we switching to a new channel?
if (idx != rfm22b_dev->channel_index) {
if (!rfm22_isCoordinator(rfm22b_dev) && rfm22b_dev->connected_timeout == 0) {
// Set the link state to disconnected.
if (rfm22b_dev->stats.link_state == OPLINKSTATUS_LINKSTATE_CONNECTED) {
rfm22b_dev->stats.link_state = OPLINKSTATUS_LINKSTATE_DISCONNECTED;
// Set the PPM outputs to INVALID
for (uint8_t i = 0; i < RFM22B_PPM_NUM_CHANNELS; ++i) {
rfm22b_dev->ppm[i] = PIOS_RCVR_INVALID;
}
}
// Stay on first channel.
idx = 0;
}
rfm22b_dev->channel_index = idx;
if (rfm22b_dev->connected_timeout > 0)
rfm22b_dev->connected_timeout--;
}
return rfm22b_dev->channels[idx];
}
/**
* Calculate what the current channel shold be.
*
* @param[in] rfm22b_dev The device structure
*/
static uint8_t rfm22_calcChannelFromClock(struct pios_rfm22b_dev *rfm22b_dev)
{
portTickType time = rfm22_coordinatorTime(rfm22b_dev, xTaskGetTickCount());
// Divide time into 8ms blocks. Coordinator sends in first 2 ms, and remote send in 5th and 6th ms.
// Channel changes occur in the last 2 ms.
uint8_t n = (time / rfm22b_dev->packet_time) % rfm22b_dev->num_channels;
return rfm22_calcChannel(rfm22b_dev, n);
}
/**
* Change channels to the calculated current channel.
*
* @param[in] rfm22b_dev The device structure
*/
static bool rfm22_changeChannel(struct pios_rfm22b_dev *rfm22b_dev)
{
// A disconnected non-coordinator modem should sit on the sync channel until connected.
if (!rfm22_isCoordinator(rfm22b_dev) && !rfm22_isConnected(rfm22b_dev)) {
return rfm22_setFreqHopChannel(rfm22b_dev, rfm22_calcChannel(rfm22b_dev, 0));
} else {
return rfm22_setFreqHopChannel(rfm22b_dev, rfm22_calcChannelFromClock(rfm22b_dev));
}
}
/*****************************************************************************
* Error Handling Functions
*****************************************************************************/
/**
* Recover from a transmit failure.
*
* @param[in] rfm22b_dev The device structure
* @return enum pios_radio_event The next event to inject
*/
static enum pios_radio_event rfm22_txFailure(struct pios_rfm22b_dev *rfm22b_dev)
{
rfm22b_dev->stats.tx_failure++;
rfm22b_dev->packet_start_ticks = 0;
rfm22b_dev->tx_data_wr = rfm22b_dev->tx_data_rd = 0;
return RADIO_EVENT_TX_START;
}
/**
* Recover from a timeout event.
*
* @param[in] rfm22b_dev The device structure
* @return enum pios_radio_event The next event to inject
*/
static enum pios_radio_event rfm22_timeout(struct pios_rfm22b_dev *rfm22b_dev)
{
rfm22b_dev->stats.timeouts++;
rfm22b_dev->packet_start_ticks = 0;
// Release the Tx packet if it's set.
if (rfm22b_dev->tx_packet_handle != 0) {
rfm22b_dev->tx_data_rd = rfm22b_dev->tx_data_wr = 0;
}
rfm22b_dev->rfm22b_state = RFM22B_STATE_TRANSITION;
rfm22b_dev->rx_buffer_wr = 0;
TX_LED_OFF;
RX_LED_OFF;
#ifdef PIOS_RFM22B_DEBUG_ON_TELEM
D1_LED_OFF;
D2_LED_OFF;
D3_LED_OFF;
D4_LED_OFF;
#endif
return RADIO_EVENT_RX_MODE;
}
/**
* Recover from a severe error.
*
* @param[in] rfm22b_dev The device structure
* @return enum pios_radio_event The next event to inject
*/
static enum pios_radio_event rfm22_error(struct pios_rfm22b_dev *rfm22b_dev)
{
rfm22b_dev->stats.resets++;
rfm22_clearLEDs();
return RADIO_EVENT_INITIALIZE;
}
/**
* A fatal error has occured in the state machine.
* this should not happen.
*
* @parem [in] rfm22b_dev The device structure
* @return enum pios_radio_event The next event to inject
*/
static enum pios_radio_event rfm22_fatal_error(__attribute__((unused)) struct pios_rfm22b_dev *rfm22b_dev)
{
// RF module error .. flash the LED's
rfm22_clearLEDs();
for (unsigned int j = 0; j < 16; j++) {
USB_LED_ON;
LINK_LED_ON;
RX_LED_OFF;
TX_LED_OFF;
PIOS_DELAY_WaitmS(200);
USB_LED_OFF;
LINK_LED_OFF;
RX_LED_ON;
TX_LED_ON;
PIOS_DELAY_WaitmS(200);
}
PIOS_DELAY_WaitmS(1000);
PIOS_Assert(0);
return RADIO_EVENT_FATAL_ERROR;
}
/*****************************************************************************
* Utility Functions
*****************************************************************************/
/**
* Calculate the time difference between the start time and end time.
* Times are in ticks. Also handles rollover.
*
* @param[in] start_time The start time in ticks.
* @param[in] end_time The end time in ticks.
*/
static uint32_t pios_rfm22_time_difference_ms(portTickType start_time, portTickType end_time)
{
if (end_time >= start_time) {
return (end_time - start_time) * portTICK_RATE_MS;
}
// Rollover
return ((portMAX_DELAY - start_time) + end_time) * portTICK_RATE_MS;
}
/**
* Allocate the device structure
*/
#if defined(PIOS_INCLUDE_FREERTOS)
static struct pios_rfm22b_dev *pios_rfm22_alloc(void)
{
struct pios_rfm22b_dev *rfm22b_dev;
rfm22b_dev = (struct pios_rfm22b_dev *)pios_malloc(sizeof(*rfm22b_dev));
rfm22b_dev->spi_id = 0;
if (!rfm22b_dev) {
return NULL;
}
rfm22b_dev->magic = PIOS_RFM22B_DEV_MAGIC;
return rfm22b_dev;
}
#else
static struct pios_rfm22b_dev pios_rfm22b_devs[PIOS_RFM22B_MAX_DEVS];
static uint8_t pios_rfm22b_num_devs;
static struct pios_rfm22b_dev *pios_rfm22_alloc(void)
{
struct pios_rfm22b_dev *rfm22b_dev;
if (pios_rfm22b_num_devs >= PIOS_RFM22B_MAX_DEVS) {
return NULL;
}
rfm22b_dev = &pios_rfm22b_devs[pios_rfm22b_num_devs++];
rfm22b_dev->magic = PIOS_RFM22B_DEV_MAGIC;
return rfm22b_dev;
}
#endif /* if defined(PIOS_INCLUDE_FREERTOS) */
/**
* Turn off all of the LEDs
*/
static void rfm22_clearLEDs(void)
{
LINK_LED_OFF;
RX_LED_OFF;
TX_LED_OFF;
#ifdef PIOS_RFM22B_DEBUG_ON_TELEM
D1_LED_OFF;
D2_LED_OFF;
D3_LED_OFF;
D4_LED_OFF;
#endif
}
/*****************************************************************************
* SPI Read/Write Functions
*****************************************************************************/
/**
* Assert the chip select line.
*
* @param[in] rfm22b_dev The RFM22B device.
*/
static void rfm22_assertCs(struct pios_rfm22b_dev *rfm22b_dev)
{
PIOS_DELAY_WaituS(1);
if (rfm22b_dev->spi_id != 0) {
PIOS_SPI_RC_PinSet(rfm22b_dev->spi_id, rfm22b_dev->slave_num, 0);
}
}
/**
* Deassert the chip select line.
*
* @param[in] rfm22b_dev The RFM22B device structure pointer.
*/
static void rfm22_deassertCs(struct pios_rfm22b_dev *rfm22b_dev)
{
if (rfm22b_dev->spi_id != 0) {
PIOS_SPI_RC_PinSet(rfm22b_dev->spi_id, rfm22b_dev->slave_num, 1);
}
}
/**
* Claim the SPI bus.
*
* @param[in] rfm22b_dev The RFM22B device structure pointer.
*/
static void rfm22_claimBus(struct pios_rfm22b_dev *rfm22b_dev)
{
if (rfm22b_dev->spi_id != 0) {
PIOS_SPI_ClaimBus(rfm22b_dev->spi_id);
}
}
/**
* Release the SPI bus.
*
* @param[in] rfm22b_dev The RFM22B device structure pointer.
*/
static void rfm22_releaseBus(struct pios_rfm22b_dev *rfm22b_dev)
{
if (rfm22b_dev->spi_id != 0) {
PIOS_SPI_ReleaseBus(rfm22b_dev->spi_id);
}
}
/**
* Claim the semaphore and write a byte to a register
*
* @param[in] rfm22b_dev The RFM22B device.
* @param[in] addr The address to write to
* @param[in] data The datat to write to that address
*/
static void rfm22_write_claim(struct pios_rfm22b_dev *rfm22b_dev, uint8_t addr, uint8_t data)
{
rfm22_claimBus(rfm22b_dev);
rfm22_assertCs(rfm22b_dev);
uint8_t buf[2] = { addr | 0x80, data };
PIOS_SPI_TransferBlock(rfm22b_dev->spi_id, buf, NULL, sizeof(buf), NULL);
rfm22_deassertCs(rfm22b_dev);
rfm22_releaseBus(rfm22b_dev);
}
/**
* Write a byte to a register without claiming the semaphore
*
* @param[in] rfm22b_dev The RFM22B device.
* @param[in] addr The address to write to
* @param[in] data The datat to write to that address
*/
static void rfm22_write(struct pios_rfm22b_dev *rfm22b_dev, uint8_t addr, uint8_t data)
{
rfm22_assertCs(rfm22b_dev);
uint8_t buf[2] = { addr | 0x80, data };
PIOS_SPI_TransferBlock(rfm22b_dev->spi_id, buf, NULL, sizeof(buf), NULL);
rfm22_deassertCs(rfm22b_dev);
}
/**
* Read a byte from an RFM22b register without claiming the bus
*
* @param[in] rfm22b_dev The RFM22B device structure pointer.
* @param[in] addr The address to read from
* @return Returns the result of the register read
*/
static uint8_t rfm22_read(struct pios_rfm22b_dev *rfm22b_dev, uint8_t addr)
{
uint8_t out[2] = { addr &0x7F, 0xFF };
uint8_t in[2];
rfm22_assertCs(rfm22b_dev);
PIOS_SPI_TransferBlock(rfm22b_dev->spi_id, out, in, sizeof(out), NULL);
rfm22_deassertCs(rfm22b_dev);
return in[1];
}
#endif /* PIOS_INCLUDE_RFM22B */
/**
* @}
* @}
*/