Raven. A homemade Atari-like computer

[PhilC]

@agranlund I don't think anyone will ever pressure you in to providing immediate support. The quickness of feedback you get from the guys is the enthusiasm to help wherever they can. Please only supply support as and when you are able to or want to

When I do finally get mine built I do want to try and help with some of the electronics and programming side of things too.

[agranlund]

Another wavetable option now with MT32 as welll:

That is so cool!
I've been wanting a standalone MT32, or MT32-Pi, for quite some time but having it on a wavetable card feels way more practical.

[troed]

I do need to be very smart about how much support for others I can actually provide during not-work without risking "burning out" on whatever the hobby project may be.

Great to see you recognizing this so clearly! This is how great projects can exist for a longer time. We're all playing around for the joy it gives us here

[PhilC]

Another wavetable option now with MT32 as welll:

I managed to snag myself an old Roland SC-55 last week, the volume knob had fallen apart but with I managed to get it all put back together.

I had one of these brand new back in the day and had forgotten just how good they are. They do a pretty good MT-32 emulation mode as well. Apparently the Yamaha MU-50 & 80 can also do this, so will dig them out and give them a try but for the £32 I paid for this Sound canvas I'm pretty much made up.

[PhilC]

Actually ~~I stand corrected on the above, the SC-55 has instruments that sound like the MT-32. ut don't do LA or the MT-32 syses stuff. Still sounds good playing monkey island theme though.

[Steve]

Actually ~~I stand corrected on the above, the SC-55 has instruments that sound like the MT-32. ut don't do LA or the MT-32 syses stuff. Still sounds good playing monkey island theme though.

Do you know you can put the SC-55 into MT32 mode? Then it re-assigns all it's internal instruments to the correct locations for MT-32. You have to hold down certain buttons when you turn it on.

[PhilC]

Actually ~~I stand corrected on the above, the SC-55 has instruments that sound like the MT-32. ut don't do LA or the MT-32 syses stuff. Still sounds good playing monkey island theme though.

Do you know you can put the SC-55 into MT32 mode? Then it re-assigns all it's internal instruments to the correct locations for MT-32. You have to hold down certain buttons when you turn it on.

I did but have yet to find out how to do so.

[PhilC]

Ok, so as well as fixing the SC-55 I dug out the Raven board, primarily to see what bits I had and what I have to order.

I might have got a bit carried away.

PXL_20240831_164004654.jpg (360.37 KiB) Viewed 390 times

Far from complete but I do have the ISA slots and probably have a pic chip for the Eiffel interface.

Re the ATF22V10, do they need to be 10ns or will 15ns do? I do have some GAL22V10 7ns if the code is compatible?

So far I think I'll need to only order about £80-100 worth of parts, thanks to the stuff I already have in stock. I'll probably order them this week but will see how nice Mr C is going to treat me this week, to see if I can get it finished soon.

Btw, does it need to be an ATF1508? I've got one but wondered if the code would fit in a 1504 as I've got about 6 of those.

[agranlund]

Re the ATF22V10, do they need to be 10ns or will 15ns do? I do have some GAL22V10 7ns if the code is compatible?

I had assumed source and pin compatibility, but having to recompile with correct toolchain and settings.
But surprisingly, it appears Atmel and Lattice fusemaps are indeed binary compatible. At least according to this post:
https://www.retrobrewcomputers.org/foru ... &#msg_5357

This guy tested that claim with an open source GAL22V10 compiler and programmed the resulting jed onto an ATF22V10C
https://mike42.me/blog/2021-10-programm ... e-software

That's actually really cool and means you could potentially ditch WinCUPL for ATF22V10/ATF16V8 stuff
I had no idea about that opensource minipro software either!

(But even if they wouldn't have been binary compatible I suppose you could recompile the cupl source with the above mentioned gal22v10 compiler)


If you already have 15ns ATF22V10 at home you could give those a try too. It's probably going to be fine.

Btw, does it need to be an ATF1508? I've got one but wondered if the code would fit in a 1504 as I've got about 6 of those.

Yep it needs the 1508 to fit.

They just recently announced end-of-life for all their PLCC variants so soon we'll only have the SMD versions left
Understandable perhaps but still a bit sad. I like the PLCC's for retro aesthetic and through hole is convenient sometimes.

[PhilC]

Thanks @agranlund I'll give those chips a try and get some of the other stuff ordered this week.

I'm going for the plcc roms as I've not had a great deal of luck with the SMT ones so far.

Hopefully more news in a week

Shame about the plcc 1508s as they really do look the part and the SMT version is very fine pitch.