Raven. A homemade Atari-like computer

[exxos]

@agranlund now you're just showing off :lol: :P

I want to know where he gets all his energy from :lol:

I think my sanity would finally break if I had to wire the databus up one more time :lol: :pullhair: :crazy:

[DoG]

CH559 seems to be popular for this kind of work. I recently built some HIDman (converts PS/2 to USB) and that project uses the same chip. ImpoSTer by Alan H also uses that chip. Alan has some program on the Atari that uploads new firmware to it and I presume through the keyboard protocol.

[agranlund]

I recently built some HIDman

Yeah that's the one partly responsible for tricking me down this path, rather than the first plan of trying to make the Eiffel firmware understand things which talks PS2 slightly faster than what it's currently reliably capable of understanding :)

I lifted pretty much all of the USB code from HIDMan leaving just PS2, joyport, ikbd etc to focus on which is nice.
The CH559 is surprisingly nice and I like how it feels appropriately old being some kind of beefed up clone of an old Intel 8051 from the 80s.

[agranlund]

Prepared the USB cabling to better visually match the rest of the computer innards.
My uATX case has two vertical slots away from the motherboard, presumably meant for gfxcard on pcie riser cable.
I'm already using one of those slots for the CF adapter and this will go in the other.

usb bracket.jpg

Before the makeover:

usb bracket original.jpg

[PhilC]

Much better in black

[agranlund]

Just received the HID prototype PCB and couldn't resist soldering it up and testing it with what I have so far in terms of firmware :)
The real version will be a bit smaller and without that extra debug/experiment header.

I put it in the old Raven.A0 board to get access to the various ports for testing but I'm hoping to find some time this weekend to plug it into the Raven.A1 so I can do the temp sensor part of the firmware.

But for now it's looking quite good;
USB mouse + keyboard works. HUB is supported too if one wants more than two ports, perhaps for future gamepad support.
PS2 mouse + keyboard works.
Legacy Atari mouse works. There will be some new IKBD command for switching between Atari and Amiga mouse mode.
Legacy Atari joysticks works.

Works, as in values look good in debug prints when interacting with the devices -- I haven't done the host<->ikbd communication code yet so from that perspective nothing is actually usable yet :)

a1hid_proto.jpg

[PhilC]

Still good progress @agranlund .

You mentioned that you have an A0 & A1, have you built an A2 as well? I might build one later in the year.

[agranlund]

Still good progress @agranlund .

I think so too and I think this is going to be really neat once finished :)

You mentioned that you have an A0 & A1, have you built an A2 as well? I might build one later in the year.

Not yet, what is set in stone so far are mostly minor fixes, plus small features.
Not enough that I have felt the need to order + build as the next version.

It's definitely going to get the Eiffel replacement directly on the board though.
And because there are ports with 2xUSB+Ethernet which would fit where the PS2 connector currently sits it could make sense to have an Ethernet chip too, freeing up an ISA slot as a nice bonus.


Some of the more outlandish ideas that would requiring significant rework I just type down in the ideas book and relegated to B0 which may happen in some distant future, or never :)

[PhilC]

@agranlund sounds like you have a few good ideas to make A2 even better.

The ethernet rom especially. My ISA card worked twice but has not worked again since, so at least the software can be tailored to the specific chip.

And decent PS/2 is getting harder to acquire, so USB would be incredibly handym

[agranlund]

And decent PS/2 is getting harder to acquire, so USB would be incredibly handym

I agree!
Many (most?) of the nice new mechanical keyboards seem to be running QMK firmware which doesn't support passive USB->PS2 adapters.

With the little Eiffel replacement I'm now able to control my desktop with USB, PS2, Legacy Atari as well as Amiga mice :)
USB and PS2 keyboards are working well too.

There's a fair bit of code remaining to support the rest of the IKBD protocol and emulate the modes it can be in, and then extra bits such as in-system firmware update, some support software etc.

But all that is just code and I'm really happy the core stuff is mostly in place and working well so far.
Probably soon time to put together and get some kind of final non-prototype version of the board made.