Partial reverse engineering of an old Z80-based card terminal
This repo is for a reverse engineered schematic and other stuff that might be helpful for developing replacement software for the Verifone Tranz 330 credit card terminal.
The Tranz 330 has a Z80 microprocessor at its heart and uses design conventions and peripherals often found in Z80 based computers. Although it's compact, it has a socketed EPROM and DIP packaged components for all but a few logic ICs, making it easy to work on. And since they do not have the security features needed for modern credit card processing bureaus, they are available cheaply on the used market.
The schematic here is a work in progress. The logic on the mainboard is almost fully mapped.
I don't plan to map the power supply, modem analog section, or all of the logically superfluous discretes (bypass caps, battery backup, etc). At some point I'll make a logical schematic of the VFD / keypad board. I want to end up with a reference that's useful for writing software and tacking on hardware.
If you want to get started writing for the Tranz 330 now, check out Big Mess O' Wires work at https://www.bigmessowires.com/2011/05/10/mapping-the-tranz-330/
Released under the Creative Commons Share Alike (CC-BY-SA) License. Share it, change it, make money on it, teach it to the children as a cautionary tale. Just make your changes public and give credit to all contributors to this project.