FreeRTOS has a strict requirement that even interrupt-safe API calls (ie.
those ending in "FromISR") can only be called from ISRs that are at lesser
or equal priorities to configMAX_SYSCALL_INTERRUPT_PRIORITY. See the
"configKERNEL_INTERRUPT_PRIORITY and configMAX_SYSCALL_INTERRUPT_PRIORITY"
section at:
http://www.freertos.org/a00110.html
The interrupt numbers used on the Cortex-M3 CPU has a somewhat backward
representation of the interrupt numbers so 255 = lowest priority and
0 = highest priority.
The calculation is further complicated by the STM32 implementation only using
the upper 4 bits of the priority value. Only 0x00, 0x10, 0x20, ..., 0xE0, 0xF0
represent useful interrupt priorities.
FreeRTOS requires that MAX_SYSCALL and KERNEL interrupt priorities are expressed
as raw unshifted 8-bit values to be programmed directly into the BASEPRI register.
The priority values passed to the NVIC initialization, however, are expected
to be 4-bit values and are shifted up by 4 within NVIC_Init() for you.
The end result is that we need this arrangement:
[highest priority]
NVIC_0 (Non-maskable-interrupt)
NVIC_1
NVIC_2
[Must NOT call FreeRTOS APIs above here]
configMAX_SYSCALL_INTERRUPT_PRIORITY (now at 48 = 0x30 = NVIC_3)
PIOS_IRQ_PRIO_HIGHEST (cur. NVIC_4)
PIOS_IRQ_PRIO_HIGH (cur. NVIC_5)
PIOS_IRQ_PRIO_MID (cur. NVIC_8)
PIOS_IRQ_PRIO_LOW (cur. NVIC_12)
configKERNEL_INTERRUPT_PRIORITY (240 = 0xF0 = NVIC_15)
[lowest priority]
The previous config had configMAX_SYSCALL_INTERRUPT_PRIORITY set at
191 (0xBF) which is effectively NVIC_11. This was allowing all of
the MID, HIGH and HIGHEST interrupt handlers to preempt the OS in
its critical sections. Since some of these ISRs were calling
FreeRTOS APIs, this would result in corrupting internal data structures
within the OS.
It should be ok to move the configKERNEL_INTERRUPT_PRIORITY to a higher
priority as long as it is less than configMAX_SYSCALL_INTERRUPT_PRIORITY.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@637 ebee16cc-31ac-478f-84a7-5cbb03baadba
PIOS_SYS: Added system reset function.
OpenPilot Makefile: Default USE_BOOTLOADER should be NO.
OpenPilot Bootloader: Removed LED initialisation.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@303 ebee16cc-31ac-478f-84a7-5cbb03baadba
Added timer usage diagram to pios_board.h
Removed bloat for extra optimisation in PIOS_DELAY.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@265 ebee16cc-31ac-478f-84a7-5cbb03baadba
You can now send and receive packets (up to 63 bytes) just like using the USART port with PIOS_COM.
HID packet length will soon be increased to support maximum UAVTalk message length.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@182 ebee16cc-31ac-478f-84a7-5cbb03baadba
Added working preliminary PIOS_USB_HID support.
Integrated PIOS_USB_HID support into PIOS_USB_HID.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@171 ebee16cc-31ac-478f-84a7-5cbb03baadba
Added PIOS_USB.
Global improvements, see specific files for changes.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@144 ebee16cc-31ac-478f-84a7-5cbb03baadba
Startup procedure now waits for SD Card with the correct settings files on it.
Refactored a few global PIOS_SDCARD names.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@140 ebee16cc-31ac-478f-84a7-5cbb03baadba
Made minGlue even more robust and simpler.
Fixed a small bug with the servo output code, which is now working 100%.
Enabled USART, which can now be used for debugging.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@138 ebee16cc-31ac-478f-84a7-5cbb03baadba
Changed bootup procedure for how the SD Card is handled.
Completed, optimised and added error handling to minGlue.c
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@137 ebee16cc-31ac-478f-84a7-5cbb03baadba
This revision is a good fall-back point as a basic test that the hardware and your development environment is working.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@133 ebee16cc-31ac-478f-84a7-5cbb03baadba
SD Card fixed and working, tested with 2Gb and 8Gb (SDHC) cards.
Changed startup_stm32f10x_HD.S to work with SysTick_Handler, needs to be changed back for FreeRTOS to work.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@132 ebee16cc-31ac-478f-84a7-5cbb03baadba
Added temporary flashing function as an easy way to know things are working.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@131 ebee16cc-31ac-478f-84a7-5cbb03baadba
init function will also try to access a file on the SDCard, this forces a real mount and will get real errors which we can handle.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@100 ebee16cc-31ac-478f-84a7-5cbb03baadba
Add some comments to pios.c so people know where the settings are loaded.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@84 ebee16cc-31ac-478f-84a7-5cbb03baadba
One major timing caveat still exists, still deciding the best way to cross that bridge.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@63 ebee16cc-31ac-478f-84a7-5cbb03baadba
Started work on BMP085 driver. Need more information from Bosch to continue.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@61 ebee16cc-31ac-478f-84a7-5cbb03baadba
New standard to be used is PIOS_Module_Function().
Likewise with OpenPilot, OP_Module_Function() is to be used.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@59 ebee16cc-31ac-478f-84a7-5cbb03baadba
