8809ae7161
At startup, buffer initial stdout / MicroyPthon banner so that it can be sent to the host on initial connection of the USB serial port. This buffering also works for when the CDC becomes disconnected and the device is still printing to stdout, and when CDC is reconnected the most recent part of stdout (depending on how big the internal USB FIFO is) is flushed to the host. This change is most obvious when you've first plugged in a MicroPython device (or hit reset), when it's a board that uses USB (CDC) serial in the chip itself for the REPL interface. This doesn't apply to UART going via a separate USB-serial chip. The stm32 port already has this buffering behaviour (it doesn't use TinyUSB) and this commit extends such behaviour to rp2, mimxrt, samd and renesas-ra ports, which do use TinyUSB. Signed-off-by: Andrew Leech <andrew@alelec.net>
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