50 lines
1.7 KiB
Markdown
50 lines
1.7 KiB
Markdown
This document describes how the STM32F1 port operates and how it can be used on
|
|
STM32-based boards, such as the "Blue Pill". STM32 MCUs are not used on any
|
|
Arduino boards, so their restrictions aren't as widely known and less straight
|
|
forward compared to common Arduino compatible boards. There aren't any standard
|
|
pin mappings either.
|
|
|
|
General considerations
|
|
======================
|
|
|
|
The port is currently designed for and tested with STM32F103xB series
|
|
MCUs, but it should work with any STM32F103 series MCUs with minimal
|
|
changes.
|
|
|
|
Unlike Arduino-based boards, typically there is no automatic reset on serial
|
|
connection with STM32 boards. Please use `restart_method: command` with the
|
|
STM32F1 port.
|
|
|
|
Fixed pins
|
|
==========
|
|
|
|
When using USB, the PA11 (D-) and PA12 (D+) pins are reserved. The USB
|
|
code assumes that PA12 (D+) has a fixed pullup resistor attached to
|
|
it.
|
|
|
|
SPI uses pins PB13/PB14/PB15, but the pins can be used as general I/O
|
|
if SPI is not used.
|
|
|
|
Digital I/O
|
|
===========
|
|
|
|
All pins that aren't part of the fixed set can be used for digital I/O. Pins are
|
|
referred to by their primary name, e.g. `PA1`. Do not try to use Arduino pin
|
|
aliases in your configuration. See ST's datasheets for more details. The
|
|
[STM32Duino](http://wiki.stm32duino.com/index.php?title=Blue_Pill) wiki has more
|
|
info on the popular "Blue Pill" board.
|
|
|
|
Analog inputs
|
|
=============
|
|
|
|
All ADC-capable pins can be used as analog inputs with the same naming as
|
|
digital I/O pins. Small packages MCUs (e.g. LFQP48) have 10 channels (PA0-PA7,
|
|
PB0-PB1), while larger package devices have 16 channels (PA0-PA7, PB0-PB1,
|
|
PC0-PC5).
|
|
|
|
SPI
|
|
===
|
|
|
|
SPI uses pin PB13 (SCK), PB14 (MISO) and PB15 (MOSI). The clock speed range is
|
|
0.15..18 MHz. Chip select pins do not have any restrictions.
|