I installed a header on the Transputer link connector on the ATW800/2 and started looking for an IDC plug/ribbon to carry the signals to the carrier board. As usual, could not find what I was looking for - and to avoid spending the rest of the weekend digging in boxes I fell back to some of those sketchy dupont connectors.
Unfortunately the dupont jumpers are far too short and this makes wiring it up really annoying. That's what happens when you can't wait a few extra days :p
To work around this I tried feeding the signals into the 2nd slot on the row, relying on the internal connections carrying that to the 1st slot in that row, where the Transputer/TRAM is actually installed. I used link 2 since its on the same row as the control signals and helps with the short wires.
I then started MUPFEL and ran rspy. I did not have success with this - it only detected the 3 Transputers usually present. However I noticed that power cycling the carrier caused the green LED on the ATW TRAM (the one it is linked through) to flicker for a few seconds.
I switched things around and moved the Transputer to the slot on the side near the ATW, fed the signals directly into the TRAM pins (these ones have small sockets on top) and tried again.
- hotwire.jpg (709.31 KiB) Not viewed yet
Powering the carrier again caused flickering on the ATW TRAM LED.
This time running rspy though...
- detected.jpg (381.4 KiB) Not viewed yet
So it has been seen by the Atari, across the external link.
It is not working reliably though in this config - rspy only detects it once. A second try shows it missing. Power cycling the carrier brings it back. I'm pretty sure the RESET net is floating on the board since my previous RE work showed it sitting at 1.6v and I kept that in mind while trying this so it's not completely unexpected that the unit would not be detected or would be flaky.
The fact it showed up at all in rspy though is a big step forward.