The Oasis BBS
AlbertGetting Started with CH32V003 Firmware in Rust
I have been working on a small project using the WCH CH32V003 and thought it would be fun to make a version of the firmware for it in Rust. I started by having a look around for hardware support and getting started guides. As it turns out, there is a HAL and hardware support by the ch32-rs project. Also, the chip is also supported by probe-rs (also see other posts tagged probe-rs). However, when it came to getting started guides, I found little other than the examples folder in the ch32-hal project. So here we are. Iβm going to rely heavily on that examples folder, but provide the step-by-step guide I was missing.
TL;DR
Here is my blinky example project: https://github.com/albertskog/ch32v003-blinky-rust.
Hardware
I used CH32V003F4P6-EVT-R0 development board and the WCH-LinkE programmer. The steps below should also work for other boards, programmers and even other CH32V chips, but I havenβt tested any.
On the CH32V003F4P6-EVT-R0, connect PD6LED1
Between CH32V003F4P6-EVT-R0 and WCH-LinkE, connect:
VCC3V3GNDGNDPD1SWDIO/TMS
0. Install Tools
First, we need to install Rust. If you came here, you probably already have (or can figure out how to do so).
We are also going to use probe-rs for uploading the binary to the device. There are different options for installing it depending on your operating system, see https://probe.rs/docs/getting-started/installation/
Iβm on a mac so I went with:
brew tap probe-rs/probe-rsbrew install probe-rs1. Project Setup
I learned we need to use Rust Nightly for some of the crates to work. I created a new project and set it up to use Nightly:
cargo new ch32v003-blinky-rustcd ch32v003-blinky-rustrustup install nightlyrustup override set nightlyWe also need the source for the standard libraries in order to build core
2. Add Configuration Files
We need a few different files to work with embedded devices.
The first is a target specification file. (Because Rust does not yet have built-in support for the RISC-V variant we need, RISCV32ec.) The file is called riscv32ec-unknown-none-elf.json and should be placed in the root of the project. I borrowed this one from the examples folder of ch32-hal:
riscv32ec-unknown-none-elf.json
Next, we need a Cargo configuration file. Create a folder called .cargo in the root of the project and in that folder, create a file called config.toml. This time, I started with the examples file but simplified as much as I could. Note that if you use a different chip, you may need to change the runner command.
.cargo/config.toml
Finally, we add some dependencies and profile settings to Cargo.toml. The ch32-hal crate is not yet published, so we grab it directly from Github. Here, the chip used is selected as a feature. Qingke is the name of the RISC-V core used in the CH32V chips, if you were wondering. We also add some profile settings. Without these, I found the binary would not fit on the chip. It is possible to add them under a separate release profile as is done in the ch32-hal examples, but then we have to remember to add --release when uploading. I found this to be easier.
Cargo.toml
3. Write Main File
Now we should have everything set up in order to write our blinky program. Here is, again, a simplified version of the ch32-hal example program:
#![no_std]#![no_main]use hal::delay::Delay;use hal::gpio::{Level, Output};use ch32_hal as hal;use panic_halt as _;#[qingke_rt::entry]fn main() -> ! { let config = hal::Config::default(); let peripherals = hal::init(config); let mut led = Output::new(peripherals.PD6, Level::Low, Default::default()); let mut delay = Delay; loop { led.toggle(); delay.delay_ms(1000); }}src/main.rs
I took out some SDI print statements which i found made the code not run on my device. The binary would upload but the LED would not blink and no messages were printed. If I figure out why, I might add another note here!
4. Run
To compile and upload, simply run
cargo runProject Files
This little blinky project is available on Github as a boilerplate and for future reference:
https://github.com/albertskog/ch32v003-blinky-rust
Hope this was helpful! π¦
Harvey Sandstrom
Poetry News