Difference between revisions of "MSV11-D/E MOS memory"
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The '''MSV11-D''' (M8044) was a [[DEC card form factor|dual]]-height [[QBUS]] [[Dynamic RAM|DRAM]] [[main memory]] card; the '''MSV11-E''' (M8045) is identical (apparently even using the same [[etch]] [[printed circuit board|PCB]]), but adds byte [[parity]]. They were used in the [[LSI-11]] [[PDP-11]]. | The '''MSV11-D''' (M8044) was a [[DEC card form factor|dual]]-height [[QBUS]] [[Dynamic RAM|DRAM]] [[main memory]] card; the '''MSV11-E''' (M8045) is identical (apparently even using the same [[etch]] [[printed circuit board|PCB]]), but adds byte [[parity]]. They were used in the [[LSI-11]] [[PDP-11]]. | ||
| − | They held 64KB when fully populated | + | They held 64KB when fully populated with 16Kx1 DRAM [[integrated circuit|chips]]. Initially they used 4Kx1 DRAMs, giving 16KB when fully populated; later/larger ones used 16Kx1 DRAMs. The memory is arranged as 2 banks, each 16 data bits (one [[PDP-11]] [[word]]) wide, optionally with 2 additional bits for [[parity]] (1 per [[byte]]) in the MSV11-E. Half-populating them (i.e. 1 bank only) produced 8KB and 322KB sized versions (depending on DRAM type). |
| − | Four versions of | + | Four versions of the parity/non-parity types exist: |
* MSV11-DA, -EA - 8KB (4K DRAMs) | * MSV11-DA, -EA - 8KB (4K DRAMs) | ||
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They had internal [[refresh]]. | They had internal [[refresh]]. | ||
| − | A card tagged "M8044-EH" has been seen; this is probably the result of a production error. The MSV11-DC is tagged 'M8044-Cx' (where 'x' varies, depending on the source of the DRAM chips used), and the MSV11- | + | A card tagged "M8044-EH" has been seen; this is probably the result of a production error. The MSV11-DC is tagged 'M8044-Cx' (where 'x' varies, depending on the source of the DRAM chips used), and the MSV11-DD is tagged 'M8044-Dx' (likewise). An "M8044-EH" thus implies it is an MSV11-DE - which does not exist. |
[[Category: QBUS Memories]] | [[Category: QBUS Memories]] | ||
Revision as of 19:46, 3 May 2020
The MSV11-D (M8044) was a dual-height QBUS DRAM main memory card; the MSV11-E (M8045) is identical (apparently even using the same etch PCB), but adds byte parity. They were used in the LSI-11 PDP-11.
They held 64KB when fully populated with 16Kx1 DRAM chips. Initially they used 4Kx1 DRAMs, giving 16KB when fully populated; later/larger ones used 16Kx1 DRAMs. The memory is arranged as 2 banks, each 16 data bits (one PDP-11 word) wide, optionally with 2 additional bits for parity (1 per byte) in the MSV11-E. Half-populating them (i.e. 1 bank only) produced 8KB and 322KB sized versions (depending on DRAM type).
Four versions of the parity/non-parity types exist:
- MSV11-DA, -EA - 8KB (4K DRAMs)
- MSV11-DB, -EB - 16KB (4K DRAMs)
- MSV11-DC, -EC - 32KB (16K DRAMs)
- MSV11-DD, -ED - 64KB (16K DRAMs)
All are Q18 (hence, could not be used in Q22 systems, such as PDP-11/23's with more than 256KB of memory).
They had internal refresh.
A card tagged "M8044-EH" has been seen; this is probably the result of a production error. The MSV11-DC is tagged 'M8044-Cx' (where 'x' varies, depending on the source of the DRAM chips used), and the MSV11-DD is tagged 'M8044-Dx' (likewise). An "M8044-EH" thus implies it is an MSV11-DE - which does not exist.
