c046b23ea2
Helps prevent the filesystem from getting formatted by mistake, among other things. For example, on a Pico board, entering Ctrl+D and Ctrl+C fast many times will eventually wipe the filesystem (without warning or notice). Further rationale: Ctrl+C is used a lot by automation scripts (eg mpremote) and UI's (eg Mu, Thonny) to get the board into a known state. If the board is not responding for a short time then it's not possible to know if it's just a slow start up (eg in _boot.py), or an infinite loop in the main application. The former should not be interrupted, but the latter should. The only way to distinguish these two cases would be to wait "long enough", and if there's nothing on the serial after "long enough" then assume it's running the application and Ctrl+C should break out of it. But defining "long enough" is impossible for all the different boards and their possible behaviour. The solution in this commit is to make it so that frozen start-up code cannot be interrupted by Ctrl+C. That code then effectively acts like normal C start-up code, which also cannot be interrupted. Note: on the stm32 port this was never seen as an issue because all start-up code is in C. But now other ports start to put more things in _boot.py and so this problem crops up. Signed-off-by: David Grayson <davidegrayson@gmail.com>
Port of MicroPython to NXP iMX RT 10xx
Currently supports Teensy 4.0, Teensy 4.1, and the MIMXRT1010_EVK, MIMXRT1020_EVK, MIMXRT1050_EVK, MIMXRT1060_EVK and MIMXRT1064_EVK boards.
Features:
- REPL over USB VCP
- machine.ADC
- machine.I2C
- machine.LED
- machine.Pin
- machine.PWM
- machine.RTC
- machine.SDCard
- machine.SPI
- machine.Signal
- machine.SoftI2C
- machine.SoftSPI
- machine.Timer
- machine.UART
- LFS2 file system at the internal Flash
- SDCard support (not on MIMXRT1010_EVK)
- Ethernet (not on Teensy 4.0 and MIMXRT1010_EVK)
Known issues:
TODO:
- More peripherals (Counter, I2S, CAN, etc)
- More Python options
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/mimxrt/ 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.
In addition newlib is required which is available for Arch Linux via the
package arm-none-eabi-newlib, for Ubuntu/Debian install package libnewlib-arm-none-eabi
Next, the board to build must be selected. Any of the board 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 SEEED_ARCH_MIX
as an example of the selected board):
$ make BOARD=SEEED_ARCH_MIX submodules
Then to build the board's firmware run:
$ make BOARD=SEEED_ARCH_MIX
The above command should produce binary images in the build-SEEED_ARCH_MIX/
subdirectory (or the equivalent directory for the board specified).
Flashing
Deploy the firmware following the instructions here https://docs.micropython.org/en/latest/mimxrt/tutorial/intro.html#deploying-the-firmware