Portability of tutorials to Upduino

[hexad]

I want to learn FPGA development and these tutorials are amazing - thank you so much!

However, there are zero available IceSticks in the market right now. A cheap and accessible FPGA is the Upduino. Is it possible that these tutorials can be transferrable to something like the Upduino?

Pardon my lack of knowledge - but this is the same reason I came across your repository.

[Mecrisp]

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 the MCH2022 badge that uses the same FPGA and the FemtoRV32-Gracilis:

https://github.com/badgeteam/mch2022-firmware-ice40/tree/master/projects/RISCV-Playground https://www.badge.team/docs/badges/mch2022/software-development/risc-v/

Maybe this gives you a starting point? There are also more simple examples if you explore the mch2022-firmware-ice40 repository a bit.

Best wishes for your journey into FPGAs that might soon become a deep rabbit hole for you to explore :-)

[Mecrisp]

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

[BrunoLevy]

Yep, it is probably quite easy to adapt icebreaker support to Upduino Internal clock is 12 MHz for both, cool

1)

  $ cd learn-fpga/FemtoRV/BOARDS
  $ cp icebreaker.mk upduino.mk
  $ cp icebreaker.pcf upduino.pcf

Edit upduino.mk, replace all instances of icebreaker with upduino (respect caps)

2) correct upduino.pcf with the correct pins fpr pclk, D1...D5, TXD,RDX and RESET

3) edit RTL/femtosoc_config.v and add a config for UPDUINO

4)

   $ cd learn-fpga/FemtoRV/RTL/configs
   $ cp icebreaker_config.v upduino_config.v

See if the reset button is negative or positive (if negative, define NRV_NEGATIVE_RESET) If nothing happens, then try maintaining RESET (if it works, it means you need to define NEGATIVE_RESET)

Normally it will be easy, the most tricky part will be finding the pin numbers for everything. The SPI Flash can be a bit tricky if you want to enable it in dual IO mode (but you can start with regular mode)

[hexad]

Thank you very much for this repo and for the support! However, i am a bit lost with the repo structure. As far as i understand the Basic folder contains some random examples (listed at the end of the main README.md). Then the main starting points are the two READMEs under the From Blinky to RISC-V category (Episode I and Episode II)? Is development of femtoRV covered in those documents? What are the Attic, Basic and FemtoRV folders? Is the FemtoRV folder the main starting point? It also contains a bunch of READMEs inside. Thank you once again and sorry for the trouble!

[BrunoLevy]

It is because there are different projects all in the same place (maybe I should create separate repositories)

• Step1: Basic it is a set of simple and self-contained projects to test a specific board, I'll start by adding a Upduino subdirectory here, and then create a Blinker
• Step 2: FemtoRV there you have a complete SOC with support for different peripherals. Add the files for your board in the BOARDS subdirectory, and add targets in the Makefile. More details here
• Step 3: From blinker to RISC-V this tutorial is meant to become a course / book on the topic. It has step by step instructions to create a pipelined RISC-V processor. It is also possible to add support for additional boards.