stephen_usher
Member
- Joined
- May 7, 2020
- Messages
- 19
I've a Sun 3/80 which whilst in storage developed a fault in the decode1 chip meaning that it can't output the /RD signal to the serial SCC. Given that this is required at an early stage in the boot the machine just flashes the LED briefly and sits there polling writing to the status register and never getting the correct data back.
Seeing these chips are not available I'm looking at the possibility of recreating it using discrete components, well a GAL or two. However, to do this i need at the very least a pinout of the chip and preferably a complete machine schematic.
The 3/80's architecture is close enough to the 3/60 to understand what the chip is supposed to be doing but too different to be actually useful.
So, does anyone have a schematic or know if one exists?
Seeing these chips are not available I'm looking at the possibility of recreating it using discrete components, well a GAL or two. However, to do this i need at the very least a pinout of the chip and preferably a complete machine schematic.
The 3/80's architecture is close enough to the 3/60 to understand what the chip is supposed to be doing but too different to be actually useful.
So, does anyone have a schematic or know if one exists?