I did not find a similar topic, but wanted to share this information to avoid other people bumping into the same issue :) I spent about two nights trying to program the iCE40HX1K-EVB using my RPi 4 with no success, checking connections, switching pins on the RPi.
Dear fellow FPGA-traveller: The PGM-1 connector does not have pin 1 in the top left corner!
(https://i.ibb.co/ZzH2xjnj/Screenshot-from-2026-06-09-11-16-50.png)
In the documentation and schematics this is rotated 180 degrees
(https://www.olimex.com/wiki/images/thumb/f/f8/ICE40PGM.jpg/650px-ICE40PGM.jpg)
The average reader: "PCB layout does not follow the schematic!!!"
I know, pebkac, this is probably due to my own experience in placing pin1 always in the same orientation on schematic/board.
I just wanted to have this highlighted somewhere :)
Also: the documentation for this board is somewhat outdated as it mentions RPi2's and some dead links at the bottom when it comes to RPi programming.
To make up for the critique of my last comment, I thought I'd help out:
Enjoy fellow travellers! https://github.com/kerstensrobin/iCE40HX1k-EVB-exploration
Scraping together some documentations and clarifying things that were not necessarily clear to me in the beginning, being out of practice when it comes to FGPA development.