- Data Path (DAP - M8390)
- Memory Controller (MCT - M8391)
- Writeable Control Store (WCS - M8394)
The three main boards are interconnected by the memory control (MC) bus (a 32 bit data path in this is used for both addresses and data). A data-handling bus called the Port Bus (again with a 32 bit data path, for data only) runs from the DAP module to the FPA and the RB730 Integrated Disk Controller. Another bus, the 8-bit wide IB bus, also runs from the DAP to the FPA. The internal memory bus runs from the MCT to the memory array modules.
- VAX-11/730 Central Processing Unit Technical Description (EK-KA730-TD-001)
- VAX-11/730 Memory System Technical Description (EK-MX730-TD-001)
- 11/730-Z Field Maintenance Print Set (MP01270) - the KA73-A Processor Module Set is covered on pp. 151-278