AE350 SoC Bare Metal Rust Examples

Everything in this repository is designed for the Sipeed Tang Mega 138K Pro board featuring the Gowin GW5AST chip along with the on-chip AndesTech AE350 A25 SoC.

Blink

Blinks the N23 led.

Features

• Using the hard AE350 IP instead of a soft one
• No DDR3 for simplicity and faster memory access
• ROM and Stack memory sections placed on SRAM
• AHB <=> SRAM speed: 200 Mhz
• 100% Rust

Compile the example with just:

# Build the project
cargo build -p blink --release
# Write the SRAM init file
just sram blink release

Then open the project in Gowin EDA and do syn, pnr, flash as usual. Or use Gowiners:

# Change dir
cd crates/blink
# Define Gowin EDA location
echo "/home/limpix/gowin" > .gowin
# Run implementation
gowiners impl
# Flash to SRAM
gowiners flash sram

Debug

Demo project to examine on-chip debugging with openocd and gdb

Warning

Do NOT burn SPI flash, as debugging requires “JTAG as regular I/O,” which means you CANNOT reconfigure the FPGA while it is configured using a bitstream with this option.

1. Build the project for debug

# Build the project with the debug profile
cargo build -p blink
# Write the SRAM init file
just sram blink debug

Then open Gowin EDA and do syn, pnr and flash as usual.

2. Run openocd

Flash the bitstream to the board and run openocd

openocd -f crates/dbg/openocd.cfg

3. Launch a debugging session

Common gdb session

# Launch remote gdb session
riscv32-unknown-elf-gdb -x debug/ae350.gdb
# Add breakpoint
hbreak blink::external_interrupt
continue
# ...

Uart

WiP