exxos's Atari, Amiga & retro forum

sety wrote: 11 Jun 2025 02:01

PhilC wrote: 10 Jun 2025 15:51 @sety did you press delete when the Atari logo is displayed at boot? You can then select which nova driver you want and then say something like 640x400x8 for 256 colours?

I did but when I select mach32 it doesn't give me any resolutions to choose from =/ It does with et4000 but I don't have one to test

Thats odd as I used a Mach32 to get started as well. Did you select the two nova options at the top of that page as well? Maybe post a pic of that bios page?

PhilC wrote: 11 Jun 2025 08:33 Thats odd as I used a Mach32 to get started as well. Did you select the two nova options at the top of that page as well? Maybe post a pic of that bios page?

It is sort of working now, but only if I hold my tongue right. Sometimes it boots, sometimes it doesn't.
I think I'm in the soup. I'm glad that it works, but I can't make it reliable. I just can't find the dependent variable, it changes every time I get home or remove and refit the board. :(

Sometimes it's "no ram in slot0" or it could be "exception error" and other times it will just boot, other times it is just crickets.

I like it better when things are binary, it either works or no. I just don't know what I've overlooked. :?

@sety I've had similar issues, you probably need to clean your Simms and simm sockets, chips and sockets with IPA. It sounds like some of the contacts are tarnished or dirty from manufacturing or from assembling.

After id done that it worked well. Actually add the ISA slots to that list too, they caused me big issues.

I have it booting reliably, but still some strange issues I can't get my head around... One problem at a time :)

The keyboard works 100% of the time, but the mouse seems to be a bit hit and miss. Probing it somehow kicks it in to gear. is the PS2 mouse clock meant to look this glitchy?



For comparison, the PS2 keyboard clock looks adorable.


Looking at the schematics there isn't anything I can see anything that would cause this. Any ideas?

Thanks :)

@sety aren't the keyboard and mouse clocks connected?

Do you have a different ps2 mouse to test with?
The clocks are (normally*) driven by the devices themselves and are separate for keyboard and mouse connectors.
PS2 protocol speed is also not 100% strict but more of an accepted range, and Im sure some devices break old recommendations. I have a usb keyboard that speaks ps2 too fast for Eiffel to keep up when using a passive usb->ps2 adapter.

(Normally, unless when the computer sends commands to the device)

PhilC wrote: 16 Jun 2025 11:29 @sety aren't the keyboard and mouse clocks connected?

That's what I thought! So I am totally confused! I can't see where I have messed up. The only thing I can think of is the PIC as I am not used to Eiffel.

agranlund wrote: 16 Jun 2025 12:46 Do you have a different ps2 mouse to test with?
The clocks are (normally*) driven by the devices themselves and are separate for keyboard and mouse connectors.
PS2 protocol speed is also not 100% strict but more of an accepted range, and Im sure some devices break old recommendations. I have a usb keyboard that speaks ps2 too fast for Eiffel to keep up when using a passive usb->ps2 adapter.

(Normally, unless when the computer sends commands to the device)

Sadly no. I only have one PS2 keyboard and mouse for my Compaq 386. (I used to have hundreds)

The locally stocked Jaycar PS2/USB adapters don't seem to work.

I have really broken something and I don't know what it is.

Voltage ripple on all lines is within spec, everything has been reworked. I don't know what I have broken. I'm thinking of starting again when v2 comes out :)

@sety just a thought, how's the ground connection on the mouse? I had a socket with a dodgy ground and it used to be intermittent as well.

For what it’s worth I can confirm this el’cheapo PS2 mouse from Amazon works here: Perixx Perimice-209P

Also the trackball on the PS2 version of Cherry G84-4400 keyboard.

Not sure I have any good ideas for what to potentially check. Mouse data+clock goes directly to the Eiffel PIC, with external pullup resistors.

I’m using USB mouse+keyboard now with an earlier protoype version of this:
https://github.com/agranlund/raven/tree ... rades/ckbd

I have not yet built that particular version, nor adjusted the firmware for it, but PCBs are supposedly
In transit so it shall be done once they arrive.
Could be an option if you can’t get the PS2 mouse working or just rather want to use USB devices?