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Code Issues Releases Activity

RFM22b: Get rid of the burst read commands and do a block transfer

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This commit is contained in:
James Cotton 2012-09-05 00:56:48 -05:00
parent 1f0004e9db
commit 527edcbee9
1 changed files with 42 additions and 46 deletions
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88
flight/PiOS/Common/pios_rfm22b.c
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@ -195,6 +195,14 @@ 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}; // 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};
/* Local function forwared declarations */
static void PIOS_RFM22B_Supervisor(uint32_t ppm_id);
@ -203,12 +211,6 @@ static void rfm22_setTxMode(uint8_t mode);
// SPI read/write functions
static void rfm22_write(uint8_t addr, uint8_t data);
static void rfm22_startBurstRead(uint8_t addr);
inline uint8_t rfm22_burstRead(void)
{
return PIOS_SPI_TransferByte(PIOS_RFM22_SPI_PORT, 0xff);
}
static void rfm22_endBurstRead(void);
static uint8_t rfm22_read(uint8_t addr);
uint8_t rfm22_txStart();
@ -692,7 +694,11 @@ static void rfm22_releaseBus()
PIOS_SPI_ReleaseBus(g_rfm22b_dev->spi_id);
}
//!
/**
* Claim the semaphore and write a byte to a register
* @param[in] addr The address to write to
* @param[in] data The datat to write to that address
*/
static void rfm22_write(uint8_t addr, uint8_t data)
{
if(PIOS_RFM22B_validate(g_rfm22b_dev)) {
@ -708,6 +714,8 @@ static void rfm22_write(uint8_t addr, uint8_t data)
/**
* Write a byte to a register without claiming the bus. Also
* toggle the NSS line
* @param[in] addr The address of the RFM22b register to write
* @param[in] data The data to write to that register
*/
static void rfm22_write_noclaim(uint8_t addr, uint8_t data)
{
@ -720,29 +728,7 @@ static void rfm22_write_noclaim(uint8_t addr, uint8_t data)
}
/**
* Start a burst read a byte from an RFM22b
* @param[in] addr The address to read from
* @return Returns the result of the register read
*/
static void rfm22_startBurstRead(uint8_t addr)
{
// wait 1us .. so we don't toggle the CS line to quickly
PIOS_DELAY_WaituS(1);
if(PIOS_RFM22B_validate(g_rfm22b_dev)) {
rfm22_claimBus();
rfm22_assertCs();
PIOS_SPI_TransferByte(g_rfm22b_dev->spi_id, addr & 0x7f);
}
}
//! Release the CS and bus
static void rfm22_endBurstRead(void)
{
rfm22_deassertCs();
rfm22_releaseBus();
}
/**
* Read a byte from an RFM22b register
* @param[in] addr The address to read from
* @return Returns the result of the register read
@ -1427,17 +1413,22 @@ void rfm22_processRxInt(void)
}
// Fetch the data from the RX FIFO
rfm22_startBurstRead(RFM22_fifo_access);
for (uint8_t i = 0; i < RX_FIFO_HI_WATERMARK; ++i)
rx_buffer[rx_buffer_wr++] = rfm22_burstRead();
rfm22_endBurstRead();
}
else
{ // just clear the RX FIFO
rfm22_startBurstRead(RFM22_fifo_access);
for (register uint16_t i = RX_FIFO_HI_WATERMARK; i > 0; i--)
rfm22_burstRead(); // read a byte from the rf modules RX FIFO buffer
rfm22_endBurstRead();
rfm22_claimBus();
rfm22_assertCs();
PIOS_SPI_TransferByte(rfm22b_dev_g->spi_id,RFM22_fifo_access & 0x7F);
rx_buffer_wr += (PIOS_SPI_TransferBlock(rfm22b_dev_g->spi_id,OUT_FF,
(uint8_t *) &rx_buffer[rx_buffer_wr],RX_FIFO_HI_WATERMARK,NULL) == 0) ?
RX_FIFO_HI_WATERMARK : 0;
rfm22_deassertCs();
rfm22_releaseBus();
} else {
// Clear the RX FIFO
rfm22_claimBus();
rfm22_assertCs();
PIOS_SPI_TransferByte(rfm22b_dev_g->spi_id,RFM22_fifo_access & 0x7F);
PIOS_SPI_TransferBlock(rfm22b_dev_g->spi_id,OUT_FF,NULL,RX_FIFO_HI_WATERMARK,NULL);
rfm22_deassertCs();
rfm22_releaseBus();
}
}
@ -1454,18 +1445,23 @@ void rfm22_processRxInt(void)
{
// read the total length of the packet data
register uint16_t len = rfm22_read(RFM22_received_packet_length);
uint32_t len = rfm22_read(RFM22_received_packet_length);
// their must still be data in the RX FIFO we need to get
if (rx_buffer_wr < len)
{
int32_t bytes_to_read = len - rx_buffer_wr;
// Fetch the data from the RX FIFO
rfm22_startBurstRead(RFM22_fifo_access);
while (rx_buffer_wr < len)
rx_buffer[rx_buffer_wr++] = rfm22_burstRead();
rfm22_endBurstRead();
rfm22_claimBus();
rfm22_assertCs();
PIOS_SPI_TransferByte(rfm22b_dev_g->spi_id,RFM22_fifo_access & 0x7F);
rx_buffer_wr += (PIOS_SPI_TransferBlock(rfm22b_dev_g->spi_id,OUT_FF,
(uint8_t *) &rx_buffer[rx_buffer_wr],bytes_to_read,NULL) == 0) ?
bytes_to_read : 0;
rfm22_deassertCs();
rfm22_releaseBus();
}
if (rx_buffer_wr != len)
{
// we have a packet length error .. discard the packet