Ardent Tool of Capitalism

The go-to place for all PS/2 and Micro Channel addicts. MAD Edition!
Reference
Material		 Software
& Drivers		 IBM
Systems		 Non-IBM
Systems		 MCA
Adapters		 Parts &
Technology		 Setup &
Config

TTL Async Adapter

@EFF8.ADF TTL Async Adapter

TTL Async Adapter

TTL Async Adapter P/N 94X0836 "TTL ASYNC CARD", Japanese design [P] [P]

F1 Fuse for 5 V supply
J1 Female DE9 connector
 U15 NS8250AN / INS8250AN UART
Y1 1.8432 MHz osc

The rest of the card is filled with through-hole 74xx logic.

All adapters I've seen had the same exact assortment of bodge wires on the solder side (see here).

Note: As the name implies, the I/O signals use TTL levels (0-5V) - not RS-232 compatible!

This adapter can be found in many PS/55 5560 machines where it was used to interface with the CADAM keypad (older version).

Content created and/or provided by:
Louis F. Ohland, Peter H. Wendt, David L. Beem, William R. Walsh, Tatsuo Sunagawa, Tomáš Slavotínek, Jim Shorney, Tim N. Clarke, Kevin Bowling, and many others.

Ardent Tool of Capitalism - MAD Edition! is maintained by Tomáš Slavotínek.
Last update: 29 Nov 2023 - Changelog | Legal Info & Contact