pico-rv32ima

Two arm cores at 133 MHz. That's already more powerful than my first computer. For $4. It qualifies as a computer on it's own. It runs Linux just a hacked version with an emulated MMU https://github.com/tvlad1234/pico-rv32ima

Very cool, happy to find out about Fuzix running on these dirt cheap SoCs (I paid 0.57€ per RP2040-Zero clone earlier this year!) And someone is even working on adding TCP/IP. I’m assuming there’s no memory protection between processes due to no MMU. It would be great to be able to use the USB port for the serial connection instead of having to connect pins for a serial port connection. There’s also https://github.com/tvlad1234/pico-rv32ima for people who are into this kind of stuff, but it requires adding SPI RAM.

maybe with a little hacking .. "Raspberry Pi Pico RISC-V Emulator Runs Linux" ( 2 days ago ) https://www.tomshardware.com/news/raspberry-pi-pico-risc-v-e... https://github.com/tvlad1234/pico-rv32ima "This project uses CNLohr's mini-rv32ima RISC-V emulator core to run Linux on a Raspberry Pi Pico. It uses two 8 megabyte SPI PSRAM chips as system memory. To alleviate the bottleneck introduced by the SPI interface of the PSRAM, a 4kb cache is used. The cache implementation comes from xhackerustc's uc32-rvima project."

The amazing part of this hack is using the SD card as main memory. And booting to a shell in 15 minutes blows the doors off the project that started it all. It uses 230 1k entries for the cache, https://github.com/tvlad1234/pico-rv32ima/blob/main/pico-rv3... It looks like it also writes 1k during each block flush. This will definitely put some pressure on the wear leveling algo on the sdcard. :) I am a big fan of this sdcard hack, I wonder what the illogical conclusion is? SDMD RAID? While it might not make it faster, adding 64Mbit of PSRAM to the other SPI port would make the sdcard live longer. https://www.sramsun.com/list-354-1.html https://www.issi.com/us/product-cellular-ram.shtml The Dmitry comments here, https://hackaday.com/2023/03/19/rp2040-runs-linux-through-ri... and has much better boot numbers for a later project. https://dmi

Woah, 375Mhz overclock, from a stock 133Mhz: https://github.com/tvlad1234/pico-rv32ima/blob/main/pico-rv3... Almost 3x, without cooling...!