Valhalla II

This is a Hello-World project for open-source VHDL synthesis on the Alhambra II FPGA (iCE40 HX4k) board. Further information on the development board can be found on the official webpage of Alhambra Bits.

Main purpose of this repository is to quickly get you started without the hassle of setting up the tool-chain yourself. For that reason, the necessary tools are provided via a Docker image over the internet. When running the script for the first time, Docker will download the required images and uses the tools from within the image. As a result, the tool versions should be relatively up-to-date, further it is not necessary to install the tool-chain on your real machine.

Get Started

1. Clone this repository
2. Connect your Alhambra II board via the USB port (use the one marked with PC on the PCB) with your computer
3. Start a terminal within this repository (it might be required to run sudo -i on Linux, in case you experience issues accessing the USB)
4. Call make prog which generates the ICE40 bitstream for the exemplary counter in src and programs your Alhambra II board.
5. Take a look at your development board, that shows the state of a binary counter on the board's LEDs, counting up every 500 ms.

Commands

• make Generates the ICE40 bitstream (runs synthesis, place and rout, and bitstream generation)
• make prog Generates the bitstream and programs the device, when connected via USB
• make clean Removes build folder of the design
• make format Optimizes the style of the VHDL code

Dependencies

Most dependencies are provided by the Docker images, therefore you do not need to install them yourself.

• Required: sudo apt install build-essential for Make
• Required: sudo apt install podman or Docker alternatively to Podman
• Optional: python3 -m pip install vsg VSG for VHDL code formatting

Thanks

The content in this repository is largely based on examples from ghdl-yosys-plugin and the similar ECP5 flow in ghdl-yosys-blink, therefore a big thanks to those projects and their maintainers.