Matthias Koch

Sorry, Bruno already mentioned that one before :-)

Welcome here! As far as I know the Upduino is based on Lattice UP5K... While not having a solution for porting Brunos complete work, I wrote a RISC-V playground for...

Wait, my error: "Icebreaker" is supported out of the box and much closer to your Upduino. But let Bruno comment on that!

Done :-)

@tcal-x Yes, PicoRV32 has PCPI, but I vote against the idea - the FemtoRV32 cores are meant to be easy to modify, and I would encourage anybody who wishes to...

Dear Bruno, you are welcome, I am glad these ideas were useful for you. If you do loads and stores with an offset relative to the zero-register x0, you get...

Same observation here, it's difficult to predict, and details sometimes change when updating to a newer Yosys release. Try to imagine how you would implement something in TTL logic gates...

Yes, it is a vanilla SPI flash chip, part number N25Q032A. https://www.micron.com/-/media/client/global/Documents/Products/Data%20Sheet/NOR%20Flash/Serial%20NOR/N25Q/n25q_32mb_1_8v_65nm.pdf If you are fluent in Forth, have a look at mecrisp-ice-1.8/hx1k/nucleus.fs for how to read a sector from...

A small intro to give you an idea and the classic introductory text: https://jeelabs.org/article/1612b/ https://www.forth.com/starting-forth/ But I think it would be much easier for you to search for Arduino code...

Here is a better datasheet. You need the "read data" command 03 (and usually the "release power-down" command AB, which you can omit on Icestick). https://www.winbond.com/resource-files/w25q128jv%20spi%20revc%2011162016.pdf