de1f1dd164
Before, both uwTick and mp_hal_ticks_ms() were used as clock source. That assumes, that these two are synchronous and start with the same value, which may be not the case for all ports. If the lag between uwTick and mp_hal_ticks_ms() is larger than the timer interval, the timer would either rush up until the times are synchronous, or not start until uwTick wraps over. As suggested by @dpgeorge, MICROPY_SOFT_TIMER_TICKS_MS is now used in softtimer.c, which has to be defined in a port's mpconfigport.h with the variable that holds the SysTick counter. Note that it's not possible to switch everything in softtimer.c to use mp_hal_ticks_ms() because the logic in SysTick_Handler that schedules soft_timer_handler() uses (eg on mimxrt) the uwTick variable directly (named systick_ms there), and mp_hal_ticks_ms() uses a different source timer. Thus it is made fully configurable. |
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|---|---|---|
| .. | ||
| boards | ||
| mcu | ||
| modules | ||
| clock_config.h | ||
| fatfs_port.c | ||
| help.c | ||
| machine_adc.c | ||
| machine_bitstream.c | ||
| machine_dac.c | ||
| machine_i2c.c | ||
| machine_pin.c | ||
| machine_pwm.c | ||
| machine_rtc.c | ||
| machine_spi.c | ||
| machine_uart.c | ||
| machine_wdt.c | ||
| main.c | ||
| Makefile | ||
| modmachine.c | ||
| modmachine.h | ||
| modsamd.c | ||
| moduos.c | ||
| modutime.c | ||
| mpconfigport.h | ||
| mphalport.c | ||
| mphalport.h | ||
| pendsv.c | ||
| pendsv.h | ||
| pin_af.c | ||
| pin_af.h | ||
| qstrdefsport.h | ||
| README.md | ||
| samd_flash.c | ||
| samd_isr.c | ||
| samd_soc.c | ||
| samd_soc.h | ||
| sections.ld | ||
| tusb_config.h | ||
| tusb_port.c | ||
Port of MicroPython to Microchip SAMD MCUs
Supports SAMD21 and SAMD51. For each supported device there is a
subdirectory in the boards/ directory.
The entry point for the specific port documentation is at https://docs.micropython.org/en/latest/samd/quickref.html, which also shows the assignment of IO-Functions to pins. The generic MicroPython documentation applies for anything not specific for the SAM port.
Due to the different flash sizes of SAMD21 and SAMD51 devices, the coverage of MicroPython modules differ. Use help("modules") to tell, which MicroPython modules are provided.
Build instructions
Before building the firmware for a given board the MicroPython cross-compiler must be built; it will be used to pre-compile some of the built-in scripts to bytecode. The cross-compiler is built and run on the host machine, using:
$ make -C mpy-cross
This command should be executed from the root directory of this repository. All other commands below should be executed from the ports/stm32/ directory.
An ARM compiler is required for the build, along with the associated binary
utilities. The default compiler is arm-none-eabi-gcc, which is available for
Arch Linux via the package arm-none-eabi-gcc, for Ubuntu via instructions
here, or
see here for the main GCC ARM
Embedded page. The compiler can be changed using the CROSS_COMPILE variable
when invoking make.
Next, the board to build must be selected. There is no default board. Any
of the names of the subdirectories in the boards/ directory is a valid board.
The board name must be passed as the argument to BOARD= when invoking make.
All boards require certain submodules to be obtained before they can be built.
The correct set of submodules can be initialised using (with
ADAFRUIT_ITSYBITSY_M4_EXPRESS as an example of the selected board):
$ make BOARD=ADAFRUIT_ITSYBITSY_M4_EXPRESS submodules
Then to build the board's firmware run:
$ make BOARD=ADAFRUIT_ITSYBITSY_M4_EXPRESS clean
$ make BOARD=ADAFRUIT_ITSYBITSY_M4_EXPRESS
The above command produces binary images in the
build-ADAFRUIT_ITSYBITSY_M4_EXPRESS/ subdirectory (or the equivalent
directory for the board specified).
Flashing the Firmware
Most SAMD21 and SAMD51 boards have a built in firmware loader. To start it, push
the reset button of the boards twice. The speed varies a little bit. If the
firmware loader starts, a drive will appear in the file manager of your PC.
Copy the created firmware.uf2 file to that drive. If the upload is finished, the
drive will disappear and the board will reboot.