Vorago VA108xx Rust Support

This crate collection provides support to write Rust applications for the VA108XX family of devices.

List of crates

This workspace contains the following released crates:

• The va108xx PAC crate containing basic low-level register definition.
• The va108xx-hal HAL crate containing higher-level abstractions on top of the PAC register crate.
• The va108xx-embassy crate containing support for running the embassy-rs RTOS.
• The vorago-reb1 BSP crate containing support for the REB1 development board.

It also contains the following helper crates:

• The bootloader crate contains a sample bootloader strongly based on the one provided by Vorago.
• The flashloader crate contains a sample flashloader which is able to update the redundant images in the NVM which is compatible to the provided bootloader as well.
• The board-tests contains an application which can be used to test the libraries on the board.
• The examples folder contains various example applications crates using the HAL and the PAC. This folder also contains dedicated example applications using the RTIC and embassy native Rust RTOSes.

The majority of the HAL implementation and the Embassy-rs support are contained in the external vorago-shared-periphs crate.

Using the .cargo/config.toml file

Use the following command to have a starting config.toml file

cp .cargo/config.toml.template .cargo/config.toml

You then can adapt the config.toml to your needs. For example, you can configure runners to conveniently flash with cargo run.

Using the sample VS Code files

Use the following command to have a starting configuration for VS Code:

cp -rT vscode .vscode

You can then adapt the files in .vscode to your needs.

Building projects

Building an application requires the thumbv6m-none-eabi cross-compiler toolchain. If you have not installed it yet, you can do so with

rustup target add thumbv6m-none-eabi

After that, you can use cargo build to build the development version of the crate. For example, you can use

cargo build --example blinky

to build a simple blinky app.

Flashing, running and debugging the software

You can use CLI or VS Code for flashing, running and debugging.

Using CLI with probe-rs

Install probe-rs first.

You can use probe-rs to run the software and display RTT log output. However, debugging does not work yet.

After installation, you can run the following command

probe-rs run --chip VA108xx_RAM --protocol jtag target/thumbv6m-none-eabi/debug/examples/blinky

to flash and run the blinky program on the RAM. There is also a VA108xx chip target available for persistent flashing.

Runner configuration is available in the .cargo/def-config.toml file to use probe-rs for convenience. probe-rs is also able to process and display defmt strings directly.

Using VS Code

Assuming a working debug connection to your VA108xx board, you can debug using VS Code with the Cortex-Debug plugin. Please make sure that objdump-multiarch and nm-multiarch are installed as well.

Some sample configuration files for VS code were provided and can be used by running cp -rT vscode .vscode like specified above. After that, you can use Run and Debug to automatically rebuild and flash your application.

If you would like to use a custom GDB application, you can specify the gdb binary in the following configuration variables in your settings.json:

• "cortex-debug.gdbPath"
• "cortex-debug.gdbPath.linux"
• "cortex-debug.gdbPath.windows"
• "cortex-debug.gdbPath.osx"

The provided VS Code configurations also provide an integrated RTT logger, which you can access via the terminal at RTT Ch:0 console. In order for the RTT block address detection to work properly, objdump-multiarch and nm-multiarch need to be installed.

Using CLI with GDB and Segger J-Link Tools

Install the following two tools first:

1. SEGGER J-Link tools installed
2. gdb-multiarch or similar cross-architecture debugger installed. All commands here assume gdb-multiarch.

You can build the blinky example application with the following command

cargo build --example blinky

Start the GDB server first. The server needs to be started with a certain configuration and with a JLink script to disable ROM protection. For example, on Debian based system the following command can be used to do this (this command is also run when running the jlink-gdb.sh script)

JLinkGDBServer -select USB -device Cortex-M0 -endian little -if JTAG-speed auto \
  -LocalhostOnly -jtagconf -1,-1

After this, you can flash and debug the application with the following command

gdb-mutliarch -q -x jlink/jlink.gdb target/thumbv6m-none-eabihf/debug/examples/blinky -tui

Please note that you can automate all steps except starting the GDB server by using a cargo runner configuration, for example with the following lines in your .cargo/config.toml file:

[target.'cfg(all(target_arch = "arm", target_os = "none"))']
runner = "gdb-multiarch -q -x jlink/jlink.gdb"

After that, you can simply use cargo run --example blinky to flash the blinky example.

Using the RTT Viewer

The Segger RTT viewer can be used to display log messages received from the target. The base address for the RTT block placement is 0x10000000. It is recommended to use a search range of 0x1000 around that base address when using the RTT viewer.

The RTT viewer will not be able to process defmt printouts. However, you can view the defmt logs by installing defmt-print first and then running

defmt-print -e <pathToElfFile> tcp

The path of the ELF file which is being debugged needs to be specified for this to work.

Learning (Embedded) Rust

If you are unfamiliar with Rust on Embedded Systems or Rust in general, the following resources are recommended:

• Rust Book
• Embedded Rust Book
• Embedded Rust Discovery
• Awesome Embedded Rust