Difference between revisions of "MS750 Memory System"
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(→VAX-11/750 Memory Controllers: add module images) |
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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 | + | 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 | + | 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 | + | * 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]] | ||
| + | <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]]. | ||
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==External links== | ==External links== | ||
Revision as of 13:29, 2 June 2022
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
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.
External links
- VAX-11/750 Memory System Technical Description (EK-MS750-TD-001)
- Comet Memory Unit Field Maintenance Print Set (MP01404) - covers the L0016
