pw_sys_io_baremetal_stm32f429 implements the
pw_sys_io facade over
The STM32F429 baremetal sys IO backend provides device startup code and a UART
driver layer that allows applications built against the
to run on a STM32F429 chip and do simple input/output via UART. The code is
optimized for the STM32F429I-DISC1, using USART1 (which is connected to the
virtual COM port on the embedded ST-LINKv2 chip). However, this should work with
all STM32F429 variations (and even some STM32F4xx chips).
This backend has no configuration options. The point of it is to provide bare- minimum platform code needed to do UART reads/writes.
This module requires relatively minimal setup:
Write code against the
dir_pw_sys_io_backendGN global variable to point to this backend.
Build an executable with a main() function using a toolchain that supports Cortex-M4.
This module provides early firmware init and a linker script, so it will conflict with other modules that do any early device init or provide a linker script.
After building an executable that utilizes this backend, flash the
produced .elf binary to the development board. Then, using a serial
communication terminal like minicom/screen (Linux/Mac) or TeraTerm (Windows),
connect to the device at a baud rate of 115200 (8N1). If you’re not using a
STM32F429I-DISC1 development board, manually connect a USB-to-serial TTL adapter
PA9 (MCU TX) and
PA10 (MCU RX), making sure to match logic
levels (e.g. 3.3V versus 1.8V).
Sample connection diagram¶
--USB Serial--+ +-----STM32F429 MCU----- | | TX o--->o PA10/USART1_RX | | RX o<---o PA9/USART1_TX | | --------------+ +-----------------------