MS11-L MOS Memory

The MS11-L is a metal oxide semiconductor (MOS) random access memory (RAM) module designed for use with the PDP-11 Unibus or compatible special buses. It stores 18-bit words (16 data bits and 2 parity bits) with a maximum capacity of 128K words. The module features parity control circuitry, a control and status register (CSR), and refresh circuitry required for its dynamic RAM storage. The manual covers technical specifications, installation (including switch and jumper configurations for memory and CSR addressing), theory of operation (detailing the timing logic, refresh logic, address decoding, and data path), and maintenance procedures (including preventive tasks and corrective troubleshooting using diagnostics).