IEU11-A/IEQ11-A

This User's Guide describes the IEU11-A and IEQ11-A, which are DMA controllers interfacing UNIBUS (VAX-11/PDP-11) or Q-Bus (LSI-11/MICRO) systems to two independent IEC/IEEE (IEC 625-1 / IEEE 488-1978) instrument buses. The document covers:

• General Description: Overview of components, application examples, functional description of bus interface messages, and specifications.
• Installation: Procedures for unpacking, module configuration (using DIP switches and jumpers), physical installation in backplanes, and verifying operation using diagnostics.
• Programming: Details on UNIBUS register sets (IEEE status, interrupt, command, data, and control registers), state diagram implementations, and service request/parallel poll functions.
• Maintenance: Troubleshooting guidance, including a flowchart and diagnostic software references for different system types.
• Appendices: Standard connections, remote message coding, handshake timing sequences, and multiline interface message bit codes.