DK8-EC Crystal Real Time Clock

This document provides comprehensive engineering information for the DK8-EC (M8830) crystal-based real-time clock module designed for the PDP-8/E processor. It includes a Master Drawing List, parts list, engineering specifications, detailed operation descriptions, and a functional block diagram. The module allows for selectable time intervals at 1 Hz, 50 Hz, 500 Hz, or 5000 Hz, configured via jumpers. The documentation also covers IOT instructions, timing requirements, operating environmental conditions, and available software support.