divinegod / stm32l0xx-hal

A hardware abstraction layer (HAL) for the STM32L0 series microcontrollers written in Rust

stm32l0xx-hal

stm32l0xx-hal is a Hardware Abstraction Layer (HAL) for the STMicro STM32L0xx family of microcontrollers.

This crate relies on Adam Greig's stm32l0 crate to provide appropriate register definitions and implements a partial set of the embedded-hal traits.

Based on the stm32l1xx-hal crate by Vitaly Domnikov and the stm32f4xx-hal crate by Daniel Egger.

Usage

Add the stm32l0xx-hal crate to your dependencies in Cargo.toml and make sure to pick the appropriate mcu-* Cargo feature to enjoy the full feature set for your MCU (see next section "Supported Configurations" for more details).

For example, when using the STM32L071KBTx MCU:

[dependencies]
stm32l0xx-hal = { version = "0.7.0", features = ["mcu-STM32L071KBTx", "rt"] }

Supported Configurations

The STM32L0 family consists of different subfamilies with different peripherals and I/O configurations. Superficially, the family can be grouped into the groups stm32l0x1, stm32l0x2 and stm32l0x3. However, some aspects like alternate function mappings for I/O pins do not follow these groups.

In order for the HAL to properly support all those MCUs, we generate some peripheral mappings and corresponding Cargo features using cube-parse.

MCU Features (mcu-*)

The easiest way for you to get started, is to use your appropriate mcu-* feature. For example, when using the STM32L071KBTx MCU, you just set the mcu-STM32L071KBTx feature in Cargo.toml:

# Cargo.toml
[dependencies]
stm32l0xx-hal = { version = "0.7.0", features = ["mcu-STM32L071KBTx", "rt"] }

If you take a look at the Cargo.toml file, you can see that mcu-STM32L071KBTx is just an alias for ["io-STM32L071", "eeprom-6144", "flash-128", "ram-20"].

I/O Features (io-*)

The io-* features are based on the GPIO peripheral version. This determines the pin function mapping of the MCU. The features seem to correspond to the product categories.

Right now, the following features are supported:

• io-STM32L021 (Product category 1)
• io-STM32L031 (Product category 2)
• io-STM32L051 (Product category 3)
• io-STM32L071 (Product category 5)

The product categories should be listed in your MCU family datasheet. The name of the io-* feature itself is derived from the internal name used in the STM32CubeMX database. It does not necessarily match the name of the MCU, for example the STM32L062K8Tx uses the GPIO peripheral version named io-STM32L051.

Memory Layout: Flash (flash-*) and RAM (ram-*)

Flash and RAM sizes are automatically configured by using the appropriate mcu-* Cargo feature, as described further up.

If you have an MCU that does not yet have a corresponding mcu-* feature, or if the default configuration is incorrect, you can override the memory.x of stm32l0xx-hal by providing your own:

In your crate root, add a file called memory.x with the correct configuration. For example:

MEMORY
{
  FLASH : ORIGIN = 0x08000000, LENGTH = 64K
  RAM : ORIGIN = 0x20000000, LENGTH = 8K
}

Add a build.rs file with the following content:

use std::env;
use std::fs::File;
use std::io::Write;
use std::path::PathBuf;

fn main() {
    // Put the linker script somewhere the linker can find it
    let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap());
    File::create(out.join("memory.x"))
        .unwrap()
        .write_all(include_bytes!("memory.x"))
        .unwrap();
    println!("cargo:rustc-link-search={}", out.display());

    println!("cargo:rerun-if-changed=build.rs");
    println!("cargo:rerun-if-changed=memory.x");
}

And finally add the disable-linker-script feature to your stm32l0xx-hal dependency:

# Cargo.toml
[dependencies]
stm32l0xx-hal = { version = "0.7.0", features = ["mcu-STM32L071K8Ux", "disable-linker-script"] }

Toolchain Setup

In order to use this HAL, you need the following Setup:

1. Install Rustup

   See rustup.rs for details. You may als be able to install Rustup directly through your distro.

2. Install the arm-none-eabi compiler toolchain

   https://developer.arm.com/open-source/gnu-toolchain/gnu-rm/downloads

   If you cannot install the toolchain directly through your OS / distro, we recommend installing the precompiled binaries to '/usr/local/opt'. Add the bin folders (/bin & /arm-none-eabi/bin) to your environments variable 'PATH'.

3. Install the thumbv6m-none-eabi target for Rust

   Simply run rustup target add thumbv6m-none-eabi

4. Install probe-run to run examples.

   cargo install probe-run

For more instructions on how to get started with ARM / Cortex-M programming using Rust, check out the Embedded Rust Book.

Build Examples

You can build examples through Cargo:

$ cargo build --release --examples --features stm32l0x1,rt

Note that not all examples are compatible with all MCUs. You might need to peek into the example source code.

Run Examples

This crate uses probe-run to run examples on target hardware.

To run the blinky example on an STM32L053 Nucleo:

cargo run --example blinky --features mcu-STM32L053R8Tx -- --chip STM32L053R8Tx

Flashing Using Helper Scripts

The following instructions outline how-to on flashing the 'serial' example code. This can be extended to any other example code.

Flashing with ST-Flash:

1. Flash the microcontroller using the flash script

   $ ./flash.sh target/thumbv6m-none-eabi/release/examples/serial
   

Flashing with OpenOCD

1. Flash the microcontroller using the openocd flash script

   $ ./openocd_flash.sh target/thumbv6m-none-eabi/release/examples/serial
   

Contributor Notes

• Revert local dependencies to external cargo and uncomment configurations before committing

License

0-Clause BSD License, see LICENSE-0BSD.txt for more details.