I bought a bunch of Z80 parts on ebay for cheap ($10 plus shipping). The parts came on a PCB which had not yet been flow soldered. From the date codes of the parts it looks like it was stuffed sometime around 1999. All I had to do was straighten some pins which were bent over to hold the parts in.
Here's the parts pulled from the card.
The parts included:
- (1) Z80 CPU @ 6 MHz
- (2) 32KB SRAMs
- (2) Z8420 Parallel I/O (PIO)
- (1) Z8430 Counter Timer Chip (CTS)
- (1) Z8470 Dual UART (DART)
The parts are all 6 MHz rated.
The only thing that is missing is an EPROM and glue logic. I will use an EEPROM so that it can be updated easily.
I want to build a retro Z80 CPU using these parts. I've already done a bunch of retro CPUs using the venerable Multicomp project by Grant Searle inside an FPGA. But I'm itching to build the "real thing" with these discrete parts.
Searching for 5V Glue Logic
I need glue logic to hook the parts up together. There are few options available nowadays for 5V glue logic. Nearly everything "out there" runs off 3.3V. Sure I could throw down a bunch of 74LSXX gates and that would work just fine. But I've gotten used to the flexibility that comes with programmable logic and I don't want a bunch of configuration jumpers. And I'm not yet sure what software I want to run so figuring out the details of the Peripheral Memory map would be a pain at the start. Plus, the ability to switch out the EPROM and run out of SRAM will introduce another bit of logic.