IBM 3270 Maintenance Manual page 663

512KB Total Memory
256KB
+
(256KB on System Board)
64/256KB Option Memory-Printer
Card Switches Adapter
(1) 64/256KB
12345678
Option with 10110001
256KB installed
(1) 12345678 1234
~ernory-Printer
10010100 0101
Adapter (128KB)
(1) 64/256KB
Adapter with
128KB installed
6-12 Maintenance Information