= LIBCH32V

== OVERVIEW

A simple Makefile based library for WCH's range of CH32Vxxx link:http://www.wch-ic.com/products/categories/47.html?pid=5[RISC-V uControllers].

There's not too much original work here, most of it has been collated from various file dumps etc. from WCH's own site and other pages.

== TOOLS SETUP

NOTE: The following assumes you are using some version of linux. It should work on mac with suitable adjustments. Not tried on windows. PRs for different platforms are welcomed.

=== GCC COMPILER

link: https://gcc.gnu.org/onlinedocs/gcc/RISC-V-Options.html

I've yet to find a known good binary build of the riscv32-unknow-* toolchain, the following shows how to build from source.

Add the following to your .bashrc or equivalent (don't forget to reload your shell).

[source,bash]

export CH32_RISCV=${HOME}/opt/ch32-riscv export RISCV_OPENOCD_WCH=${HOME}/opt/riscv-openocd-wch export PATH=${PATH}:${CH32_RISCV}/bin:${RISCV_OPENOCD_WCH}/bin

==== GCC build prerequisites .Debian/Ubuntu [source,bash]

sudo apt-get install autoconf automake autotools-dev curl python3 python3-pip python3-tomli libmpc-dev libmpfr-dev libgmp-dev gawk build-essential bison flex texinfo gperf libtool patchutils bc zlib1g-dev libexpat-dev ninja-build git cmake libglib2.0-dev libslirp-dev bear

.Arch Linux (incomplete?) [source,bash]

sudo pacman -Syu curl python3 libmpc mpfr gmp base-devel texinfo gperf patchutils bc zlib expat libslirp bear hidapi libjaylink

.Fedora/Rocky/RHEL [source,bash]

sudo yum install autoconf automake python3 libmpc-devel mpfr-devel gmp-devel gawk bison flex texinfo patchutils gcc gcc-c++ zlib-devel expat-devel libslirp-devel bear libgudev-devel libusb-devel hidapi hidapi-devel

==== Obtain and build gcc

[source,bash]

Clone master branch

git clone --branch master https://github.com/riscv/riscv-gnu-toolchain ~/github.com/riscv/riscv-gnu-toolchain cd ~/github.com/riscv/riscv-gnu-toolchain

Configure build, the --with-* options seem to be correct for the WCH CH32V range of uControllers

./configure --prefix=${CH32_RISCV} --with-arch=rv32g --with-abi=ilp32

Build and install

make -j$(nproc)

Test

riscv32-unknown-elf-gcc --version

Output should be something like this

riscv32-unknown-elf-gcc () 14.2.0 Copyright (C) 2024 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

=== WLINK

I use the excellent link:https://github.com/ch32-rs/wlink[wlink] to flash the uController.

==== WLINK prerequisites

.WCH-Link udev rules [source,bash]

udev rule for programmer

sudo cp run/60-libch32v.rules /etc/udev/rules.d/60-libch32v.rules

reload rules

sudo udevadm control --reload-rules

==== WLINK install

At the time of writing, wlink v0.1.1 was the latest released version. I suggest checking the link:https://github.com/ch32-rs/wlink/releases[release page] to see if that's changed.

.Installtion of wlink v0.1.1 [source,bash]

Get and unpack required version

cd /tmp wget https://github.com/ch32-rs/wlink/releases/download/v0.1.1/wlink-v0.1.1-linux-x64.tar.gz tar -xf wlink-v0.1.1-linux-x64.tar.gz

Copy wlink binary to somewhere in your $PATH (I use ${HOME}/.local/bin)

mkdir -p ${HOME}/.local/bin cp wlink-linux-x64/wlink ${HOME}/.local/bin

Test

wlink list

You should get something like the following (assuming you have a WCH-Link adapter connected)

<WCH-Link#0 libusb device> Bus 001 Device 004 ID 1a86:8010(USB-FS 12 Mbps) (RV mode)

=== OPENOCD

I've forked link:https://github.com/Seneral/riscv-openocd-wch to provide a somewhat stable openocd build.

==== Obtain and build [source,bash]

git clone https://github.com/nj-designs/riscv-openocd-wch.git ${HOME}/github.com/nj-designs/riscv-openocd-wch cd ${HOME}/github.com/nj-designs/riscv-openocd-wch ./bootstrap ./configure --prefix=${RISCV_OPENOCD_WCH} --program-prefix=wlink- --enable-wlink --disable-werror make -j$(nproc) make install

As an alternative, I've included a a build of openocd in the run dir.

== BASIC WORKFLOW

Once all of the tools above are install/configured, you can build and test a version of blinky as follows.

=== BUILD

To build, simply run make in the root of this repo.

If all goes well, the last few lines of output should look something like this: [source,bash]

Linking... riscv32-unknown-elf-gcc -std=gnu2x -march=rv32imac_zicsr -mabi=ilp32e -ffreestanding -fno-pic -Os -Werror -g -Wall -Wextra -Ilib/include -Ibuild -DAPP_STDOUT_BUFFER_SIZE=1024 -DAPP_PROVIDE_PRINTF=1 -DAPP_PRINTF_DISABLE_SUPPORT_FLOAT -DAPP_PRINTF_DISABLE_SUPPORT_EXPONENTIAL -DAPP_PRINTF_DISABLE_SUPPORT_LONG_LONG -DAPP_HSE_FREQ=16000000 -DAPP_SYSCLK_FREQ=48000000 -DWCH_CH32V203G6U6=0x96ef63e9 -DLIBCH32_DEVICE_ID=WCH_CH32V203G6U6 -DLIBCH32_DEVICE_NAME="CH32V203G6U6" -DLIBCH32_FAMILY="v203" -DLIBCH32_FLASH_PROG_ADDR=0x08000000 -DLIBCH32_FLASH_SIZE=32768 -DLIBCH32_FLASH_START=0x00000000 -DLIBCH32_HAS_ADC1=1 -DLIBCH32_HAS_ADC2=1 -DLIBCH32_HAS_ADTM1=1 -DLIBCH32_HAS_GPIOA=1 -DLIBCH32_HAS_GPIOB=1 -DLIBCH32_HAS_GPIOD=1 -DLIBCH32_HAS_GPTM2=1 -DLIBCH32_HAS_GPTM3=1 -DLIBCH32_HAS_GPTM4=1 -DLIBCH32_HAS_I2C1=1 -DLIBCH32_HAS_SPI1=1 -DLIBCH32_HAS_USART1=1 -DLIBCH32_HAS_USART2=1 -DLIBCH32_LD_SCRIPT="ch32v.ld" -DLIBCH32_MABI="ilp32e" -DLIBCH32_MARCH="rv32imac_zicsr" -DLIBCH32_SRAM_SIZE=10240 -DLIBCH32_SRAM_START=0x20000000 -DLIBCH32_SYS_TICK_WIDTH=64 -ffunction-sections -fdata-sections build/lib/src/reset.o build/lib/src/v203/vector-v203.o build/app/led-flash/led-flash.o build/lib/src/adc.o build/lib/src/adtm.o build/lib/src/afio.o build/lib/src/core.o build/lib/src/dma.o build/lib/src/gpio.o build/lib/src/gptm.o build/lib/src/i2c.o build/lib/src/init.o build/lib/src/list_mgr.o build/lib/src/printf.o build/lib/src/rcc.o build/lib/src/spi.o build/lib/src/stdout-buffered.o build/lib/src/usart.o -Wl,-Map,build/led-flash.map -nostdlib -nodefaultlibs -nolibc -nostartfiles -Wl,--no-relax -Wl,--gc-sections -Wl,--defsym=RAM_ORIGIN=0x20000000 -Wl,--defsym=RAM_LENGTH=10240 -Wl,--defsym=FLASH_ORIGIN=0x00000000 -Wl,--defsym=FLASH_LENGTH=32768 -Wl,-Tlib/ld/link.ld --output build/led-flash.elf riscv32-unknown-elf-size -A -x build/led-flash.elf build/led-flash.elf : section size addr .init 0x4 0x0 .vector 0xfc 0x4 .text 0x69c 0x100 .fini 0x0 0x79c .dalign 0x0 0x20000000 .dlalign 0x0 0x79c .data 0x8 0x20000000 .bss 0x30 0x20000008 .stack 0x800 0x20002000 .gptm2 0x50 0x40000000 .gptm3 0x50 0x40000400 .gptm4 0x50 0x40000800 .usart2 0x1c 0x40004400 .i2c1 0x22 0x40005400 .afio 0xc 0x40010000 .gpio_a 0x1c 0x40010800 .gpio_b 0x1c 0x40010c00 .gpio_d 0x1c 0x40011400 .adc1 0x50 0x40012400 .adc2 0x50 0x40012800 .spi1 0x22 0x40013000 .adtm1 0x50 0x40012c00 .usart1 0x1c 0x40013800 .dma1 0xa8 0x40020000 .rcc 0x30 0x40021000 .pfic 0xd14 0xe000e000 .systick 0x18 0xe000f000 .riscv.attributes 0x54 0x0 .comment 0xf 0x0 .debug_line 0x2835 0x0 .debug_info 0x66b5 0x0 .debug_abbrev 0x1885 0x0 .debug_aranges 0x2f8 0x0 .debug_str 0x3660 0x0 .debug_ranges 0x20 0x0 .debug_loclists 0xa69 0x0 .debug_rnglists 0x239 0x0 .debug_line_str 0x1f9 0x0 .debug_frame 0x4b0 0x0 Total 0x11529

riscv32-unknown-elf-objdump -h -S -C build/led-flash.elf > build/led-flash.lst

riscv32-unknown-elf-nm -n build/led-flash.elf > build/led-flash.sym

riscv32-unknown-elf-objcopy -O binary build/led-flash.elf build/led-flash.bin

=== PROGRAM

To program what's just been built.

[source,bash]

make flash

=== DEBUG

If you want to debug your program, first flash your code to the device using make flash.

.Start the openocd [source,bash]

wlink-openocd -f run/wch-riscv.cfg -c init -c halt -c wlink_reset_resume

or

./run/openocd -f run/wch-riscv.cfg -c init -c halt -c wlink_reset_resume

.Start and connect GDB [source,bash]

make start-gdb

== TODO

• Improve RCC setup
• Introduce concept of boards to build system
• Add ini file as a build dependency

== Links

link:https://clang.llvm.org/docs/ClangFormatStyleOptions.html

link:https://github.com/wuxx/nanoCH32V203[nanoCH32V203]