The "8445" number is a date code. 84 means 1984 and 45 means week 45 of that year. The weeks normally count from January up to December.
The -65 is a number for ULAs that go up with new production runs. Normally a larger number means later part. But the newer parts should be backwards compatible.
ULA chips do run hot. Internally they use logic that runs at a voltage that just under 1V. So the chips have a built-in voltage regulators. Plus the logic is based on bipolar technology which runs hot when designed for high speed logic.
I need to get my head around the rest of your post...
But all analogue (or TTL) video displays need a sync signal. For composite and UHF, it's part of the video signal. But for the type of RGB used by Acorn 8 bit computers, it's a separate signal.
The +5V output pin can be ignored and left unconnected if feeding a VGA device.
Mark
The -65 is a number for ULAs that go up with new production runs. Normally a larger number means later part. But the newer parts should be backwards compatible.
ULA chips do run hot. Internally they use logic that runs at a voltage that just under 1V. So the chips have a built-in voltage regulators. Plus the logic is based on bipolar technology which runs hot when designed for high speed logic.
I need to get my head around the rest of your post...
But all analogue (or TTL) video displays need a sync signal. For composite and UHF, it's part of the video signal. But for the type of RGB used by Acorn 8 bit computers, it's a separate signal.
The +5V output pin can be ignored and left unconnected if feeding a VGA device.
Mark
Statistics: Posted by 1024MAK — Sat Jan 18, 2025 6:18 pm