I knew I doggedly stuck with 18.04 for good reason!

Dave

hoglet -- well, it is not a problem with the preloaded library. Works like a charm, but scared me for a few minutes.

Just one of the many bizzare problems to solve.

Apparently I must enjoy it, or I'd be doing something else, I suppose.

I am back at my lab, on a slightly-more-modern 8th-gen I7, and am happy to report that my build times are just under 20 seconds using the IDE (for my Tugman CPU SOC, it is under 10 seconds!).

I am in the process of reinstalling the opensource yosys/apycula/nextpnr toolchain and will report when I get that working. God knows I've installed it enough. Maybe this time I'll be able to get nextpnr-gowin to work in graphics mode (himbaechel does not, and my previous attempt with nextpnr-gowin in GUI mode crashes my laptop), and finally see the FPGA.

Also -- I found my password for enso, so I will be phasing out enso1 (I swore I tried that password many times!)

I have many other good news to report, but first I have to get settled in.

_________________
In theory, there is no difference between theory and practice. In practice, there is. ...Jan van de Snepscheut

Looking forward to updates from the original enso!

Warning: original enso is just as grouchy as enso1!

_________________
In theory, there is no difference between theory and practice. In practice, there is. ...Jan van de Snepscheut

Free Toolchain Notes
The free toolchain is an amazing achievement, but it has its issues.

It is slow. My Tugman project (an 18-bit CPU SOC taking up about 500 LUTs, ~6% of FPGA resources), builds in the Chinese IDE in 10 seconds flat on an 8th-gen I7 box. The free toolchain took 4 times as long. So I will not be using it for iterative develpment.

But it is a flexible tool for digging into the FPGA, viewing it in a way not possible in the IDE, and performing experiments to supplement our understanding of how it is wired up internally.

In particular, with some cajoling, it is possible to pull up an 'FPGA Editor'-like view of the fpga and trace BELs and wires.

But in order to do so, you need to use nextpnr-gowin (instead of the more up-to-date nextpnr-himbaechel) in --gui mode (because nextpnr-himbaechel does not show anything in gui mode!), and you need to patch nextpnr-gowin prior to compiling to prevent crashes... Yeah, I almost gave up on it but then figured it out anyway. The patch is documented here: https://github.com/rfuest/nextpnr/commit/e4c09a1011f2df9b77f9360f14f58af6ab1f5e1c.

Anyway, the best starting point if you want to use it with Gowin is https://learn.lushaylabs.com/os-toolchain-manual-installation/, except you want to add -DBUILD_GUI=ON (and make sure qt5 dependencies are met -- read the README.md). Also, build nextpnr-himbaechel, since you will be using that mostly, without gui).

There are a few hazards ahead -- getting the damn Python and pyenv to work, and in my case, having to `export LD_LIBRARY_PATH=~/.pyenv/versions/3.9.13/lib` anyway for some reason. I hate Python -- the most unstable crap language there is, but everything depends on it. When some jackass who maintains an unknown library decides to change the name of some variable from current_version to current-version, everything comes crashing down.

Apycula, the project reverse-engineering Gowin, has some interesting documentation, worth looking at on github.

https://github.com/YosysHQ
https://github.com/YosysHQ/nextpnr
https://github.com/YosysHQ/apicula

_________________
In theory, there is no difference between theory and practice. In practice, there is. ...Jan van de Snepscheut

Command-line builds using GOWIN tools

Gowin tools have a built-in Tcl scripting capability. In particular, the binary gw-sh is a command-line version of the toolchain, which allows you to manually load the files, configure options, and run synthesis and/or pnr.

This would be very tedious, but you can send it a script containing something like:


If you find that tedious, just open an IDE project like you always do, select 'console' at the bottom, and enter saveto script.tcl (use a name that would make sense, of course). It will have everything except the final run all, which you should add yourself.

See the appropriate manual (SUG100-4.1E_Gowin Software User Guide.pdf), and explore by dumping your project from the IDE, using saveto -all_options <filename>. You may have to remove some options that cause errors for some reason, but you get the idea.

For an extra credit, create a Makefile. Now you are a real power user.

_________________
In theory, there is no difference between theory and practice. In practice, there is. ...Jan van de Snepscheut

I'm running out of steam.

I cleaned up my 65c02 system -- it now contains the bitstream, so you can

* load the provided .fs bitstream with OpenFPGALoader or whatever;
* build using the opensource toolchain with the attached Makefile;
* build using the GOWIN IDE - the project file is attached;
* build using GOWIN's gw-sh command-line tcl tool, using the attached tcl script.

https://tildegit.org/stack/Tangnano9K-65c02-experiments

_________________
In theory, there is no difference between theory and practice. In practice, there is. ...Jan van de Snepscheut