Difference between revisions of "MS750 Memory System"

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(VAX-11/750 Memory Controllers: add module images)
(add image of backplane, showing memory slots - explain division between memory and CPU slots)
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[[File:VAX-11750_Backplane.JPG|300px|thumb|right|/750 backplane from behind, showing the slots occupied by the MS750 in the centre]]
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The '''MS750 Memory System''' is the [[main memory]] for the [[VAX-11/750]]; it consists of:
 
The '''MS750 Memory System''' is the [[main memory]] for the [[VAX-11/750]]; it consists of:
  
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* one to eight Memory Modules
 
* one to eight Memory Modules
  
The Memory Controller is a [[CMI]] Module, either L0011, L0016, or L0022 placed in CMI Slot 10.
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The Memory Controller connects to the [[CPU/Memory Interconnect]] [[bus]]; the Controller Module (either L0011, L0016, or L0022) resides in a custom slot in the [[Central Processing Unit|CPU]] [[backplane]], 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.
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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==
 
==VAX-11/750 Memory Controllers==
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* L0011 - up to eight [[M8728]] 256KB Memory Modules = 2MB max.
 
* L0011 - up to eight [[M8728]] 256KB Memory Modules = 2MB max.
 
* L0016 - up to eight [[M8750]] 1MB Memory Modules = 8MB 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.
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* 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)
 
(14MB of Memory is the architectural limit of the VAX-11/750)
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[[Image:1MBMemoryArray.jpg|thumb|200px|left|1MB module]]
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<br clear=all>
  
 
The earlier modules are also used with the [[MK11 memory system]] of the [[PDP-11/70]].
 
The earlier modules are also used with the [[MK11 memory system]] of the [[PDP-11/70]].
 
[[Image:1MBMemoryArray.jpg|thumb|200px|left|1MB module]]
 
  
 
==External links==
 
==External links==

Revision as of 13:29, 2 June 2022

/750 backplane from behind, showing the slots occupied by the MS750 in the centre

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 connects to the CPU/Memory Interconnect bus; the Controller Module (either L0011, L0016, or L0022) resides in a custom slot in the CPU backplane, 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)

1MB module


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

External links