Lattice ICE40 FPGA

FreeWili2 carries the same proven Lattice ICE40 FPGA as FreeWili1 — and it’s a pretty amazing device. There are tasks the RP2350 can’t handle well, even with PIO and dual cores, and the ICE40 covers them cleanly. SPI slave simulation is a prime example of the kind of cycle-accurate work only programmable logic can do reliably.

The FPGA is backed by 8 MB of dedicated SRAM, giving it substantial working memory for logic-intensive workloads. The optional Linux CM0 module connects directly to the ICE40, so software running on Linux has a fast, low-latency path into the programmable fabric.