Major Registers (PDP 8/E)

This document consists of the technical engineering schematics for the M8300 "Major Registers" circuit board used in the Digital Equipment Corporation (DEC) PDP-8/E computer.

The document includes:

• A physical layout diagram (Page 1) detailing the component placement, pin connections, and power distribution for the board.
• Detailed logic schematics (Pages 2–5) covering the registers, data bus routing, and control logic. The schematics show the implementation of the registers across different bit-ranges (bits 0-1, 2-5, 6-8, and 9-11), utilizing integrated circuits such as the 7483 (adders), 74151/74153 (multiplexers), 8266 (data selectors), and 8235 (registers) to facilitate core processor operations.

The boards are designed to handle major computational register functions, data bus interface logic, and control signals necessary for the operation of the PDP-8/E architecture.