Raven. A homemade Atari-like computer

[agranlund]

@agranlund I'm wanting to start experimenting with programming the Raven, what are you using for your programming environment? Do you use the Raven now for programming or something like VSCode?

A little bit of a mix.
The bootrom + emutos are cross compiled with gcc on my Mac.

But for most of the supporting software I try to choose PureC where it feels reasonable to do so.
Mainly so that I can have a nice retro experience programming directly on Raven which I enjoy :)
(though everything is set up so you can cross compile even PureC projects from a real PC too)

If you are interested in the rom code, or source for any of the other softwares for Raven then have a look in the github sw folder:
https://github.com/agranlund/raven/tree/main/sw

The readme.md file at the root lists what compilers are used for what things.
Apart from compiler setup, everything should be included and ready to build using their makefiles.
Everything can be cross compiled from a normal computer but I have only done so from my Intel Mac so your mileage may vary.
For GCC I use Thorsten Ottos version 13.3.0 (https://tho-otto.de/crossmint.php) and the PureC compiler needs a one-time setup described in the readme inside sw/purec.

If you are interested in building "srec" programs, small bare-metal programs that you can run from the boot monitor before the OS has started, then there are some tiny examples in the folder "sw/rom/srec".

[PhilC]

Thank you @agranlund, that will give me a good starting point. As long as I can get stuff working on an M series Mac as well that is :lol:

[danboid]

About that dwindling, overpriced supply of Raven friendly ISA graphics cards. Isn't this where the FPGAs step in?

Are there not any suitable bitstreams (FPGA "firmware") that we could run on something like the Graphics Gremlin HDMI?

https://github.com/yeokm1/graphics-gremlin-hdmi

It seems that can only handle CGA and MDA currently and we need something SVGA capable for the Raven.

There seems to be quite a lot of excitement on here recently about the ATW800/2 which seems to offer enhanced graphics to MegaST(e) and TT users so could we not mount one of these cheap Tang Nano FPGAs (they're great btw) on a custom ISA card and modify the GPU bitstream used by the ATW800, presuming that its open source, to get us an affordable FPGA graphics card for the Raven?

The Tang Nano 20K FPGAs that let you simulate a STe or an Amiga 500 cost less than £30.

[PhilC]

@danboid at the moment we rely on @agranlund and his his gracious allowance of time and skill to support what we have so far.

I for one would love to see lots of new things for the Raven but know for this to be the case, it will mean that others, including myself, need to step up and do some if that coding, experimenting etc.

Still, it is a good suggestion. How's your programming skills?

[danboid]

It is merely a suggestion for discussion. I would like to hear what Anders has to say about the graphics gremlin and the AT800 and how these could potentially be used by the Raven. I searched the forum and I only found one mention of the GG and it wasn't in any of the Raven topics so here I am introducing it as a potential fix, or part of a solution, to the Raven's graphics card supply issue.

I'm well aware Anders is one man doing this as a hobby. My engineering skills are fledgling at best. I have nothing but respect and adulation for what Anders has achieved. Please don't take my brainstorming as pressure or a threat.

I spend most of my free time contributing to open source projects, I have no experience with FPGA dev but I'd like to learn. Knocking up a FPGA graphics card is well over my pay grade.

[Oldskool]

What is the graphic card issue? There are lots of et4k cards…

[danboid]

I've just had a search on ebay for et4000 and they seem to average about £120.

I'm far from being an FPGA expert but I suspect that if the Tang Nano 20K can simulate an STe with 8 MB RAM and IDE hard disk etc it could also very likely simulate a et4k or better graphics card and then we might be able to get a bitstream upgradable graphics card for likely less than £50 and you can be more certain of it working that a card from ebay that probably hasn't been used for 30+ years.

I think it that'd be a great boon to the project personally although I do sympathise with those wanting to keep the system more retro and hence FPGA free. I'm not keen on sticking a Pistorm in my Amiga because it seems like I'm cheating and I like not using Linux etc on retro hardware.

[Cyprian]

I'm far from being an FPGA expert but I suspect that if the Tang Nano 20K can simulate an STe with 8 MB RAM and IDE hard disk etc it could also very likely simulate a et4k or better graphics card

ATW800/2 uses Tang Nano 20K as an accelerated graphics card

[agranlund]

I couldn't resist.. expecting it could be a pretty fun and quick(?) project making a Tos driver for floppy disk on the isa bus when it arrives.
It comes with IDE, parallel and two serial ports too but I'm not sure I need many more of those things :lol:

s-l1600.jpg

(Yes, I am fully aware of how pointless it is :))

[danboid]

I couldn't resist.. expecting it could be a pretty fun and quick(?) project making a Tos driver for floppy disk on the isa bus when it arrives.
It comes with IDE, parallel and two serial ports too but I'm not sure I need many more of those things :lol:

s-l1600.jpg

(Yes, I am fully aware of how pointless it is :))

I love it!

It'd be great if we could boot emutos from a floppy on the Raven.

Great work Mr G!