Ardent Tool of Capitalism

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Reference
Material		 Software
& Drivers		 IBM
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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 collected 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 is maintained by Tomáš Slavotínek.
Last update: 07 Dec 2024 - Changelog | About | Legal & Contact