LED to believe

This project aims to provide LED blinking examples for all the FPGA dev boards in the world.

The goal is to provide a quick way to test your new FPGA board and get acquainted with using FuseSoC in your design flow.

Each FPGA board is implemented as a separate FuseSoC target and users are highly encouraged to add support for their any board at their disposal so that we can have a large collection.

How to use

This project is available in the FuseSoC base library, so if you have FuseSoC installed, you likely already have this project as well.

To check if it's available run fusesoc core list and check for a core called fusesoc:utils:blinky.

If it's not there, try to run fusesoc library update to refresh the core libraries and look again.

If it's still not there, or if you want to modify the project, e.g. to add support for an additional board, you can add LED to believe as a new core library with fusesoc library add blinky git clone https://github.com/fusesoc/blinky. LED to believe will now be added as a new library and downloaded to fusesoc_libraries/blinky

To build for your particular board, run fusesoc run --target=<board> fusesoc:utils:blinky where <board> is one of the boards listed in the Board support section below.

Alternatively, run fusesoc core show fusesoc:utils:blinky to find all available targets.

There is also a simulation target available to test the core without any hardware. To use this, run fusesoc run --target=sim fusesoc:utils:blinky.

The simulation target has a number of target-specific configuration parameters that can be set. All target-specific parameters goes on the end of the command line (after the core name).

To list all simulation parameters, run fusesoc run --target=sim fusesoc:utils:blinky --help.

Example: To run four pulses with a simulated clock frequency of 4MHz and creating a VCD file, run fusesoc run --target=sim fusesoc:utils:blinky --pulses=4 --clk_freq_hz=4000000 --vcd.

The default simulator to use is Icarus Verilog, but other simulators can be used by setting the --tool parameter after the run command.

Currently supported simulators for this target are icarus, modelsim and xsim. To use e.g. modelsim run fusesoc run --target=sim --tool=modelsim fusesoc:utils:blinky.

What to do next

That was fun, wasn't it? And did you know that once you have gotten a LED to blink in this way, you are actually 90% of the way already to run a small SoC with a RISC-V CPU on the same board. Maybe your board is already supported? Or maybe you're up to the challenge of adding support for it. All it takes is to create a 16MHz clock and allocate an output pin to connect a UART. For more info, move on to learn about and run SERV, the world's smallest RISC-V CPU