MS750 Memory System

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The MS750 Memory System is the main memory for the VAX-11/750; it consists of:

  • one Memory Controller (MCM)
  • one to eight Memory Modules

The Memory Controller is a CMI Module, either L0011, L0016, or L0022 placed in CMI Slot 10.

The Memory Modules have their own backplane slots (the physical backplane itself, DEC part number 50-13821/70-16486, is shared with the CPU), 8 slots in total.

VAX-11/750 Memory Controllers

256KB module

There were three different Memory Controller Modules for the MS750:

  • L0011 - up to eight M8728 256KB Memory Modules = 2MB max.
  • L0016 - up to eight M8750 1MB Memory Modules = 8MB max.
  • L0022 - up to two M7199 4MB Memory Modules and six M8750 1MB Memory Modules = 14MB max.

(14MB of Memory is the architectural limit of the VAX-11/750)

The earlier modules are also used with the MK11 memory system of the PDP-11/70.

1MB module

External links