Difference between revisions of "MM11-K core memory"
(extend slightly) |
(Add jumper details and function) |
||
| Line 8: | Line 8: | ||
The MM11-K also includes an 8 Kbyte H213 quad-format [[core memory]] stack card, instead of the 16 Kbyte H214 card of the MM11-L. It uses all the same custom [[backplane]]s as the MM11-L. | The MM11-K also includes an 8 Kbyte H213 quad-format [[core memory]] stack card, instead of the 16 Kbyte H214 card of the MM11-L. It uses all the same custom [[backplane]]s as the MM11-L. | ||
| − | On the G110 module, two jumpers (W9 and W10) are set depending on whether it is being used with a 8 Kbyte or a 16 Kbyte core stack; | + | On the G110 module, two jumpers (W9 and W10) are set depending on whether it is being used with a 8 Kbyte or a 16 Kbyte core stack; for the MM11-K, W9 is installed, and W10 is removed. On the G231 module, two other jumpers (J3 and J4) are similarly set depending on the size; for the MM11-K, J3 is in, and J4 is out. |
| + | |||
| + | The effect of these jumpers is to send bus address line A13 to the 'device selector' circuitry, along with A14-A17, in the MM11-K (it goes to 'Decode X-switches', along with A10-A12, in the MM11-L). | ||
==Documentation== | ==Documentation== | ||
Revision as of 01:03, 23 February 2018
MM11-K core memory is a rare UNIBUS main memory system which is effectively an earlier, smaller version of the common MM11-L core memory.
Like the MM11-L, it consists of three cards, two of them the same as those of the MM11-L:
- G110 - hex-format memory control logic and data channels
- G231 - hex-format memory driver logic
The MM11-K also includes an 8 Kbyte H213 quad-format core memory stack card, instead of the 16 Kbyte H214 card of the MM11-L. It uses all the same custom backplanes as the MM11-L.
On the G110 module, two jumpers (W9 and W10) are set depending on whether it is being used with a 8 Kbyte or a 16 Kbyte core stack; for the MM11-K, W9 is installed, and W10 is removed. On the G231 module, two other jumpers (J3 and J4) are similarly set depending on the size; for the MM11-K, J3 is in, and J4 is out.
The effect of these jumpers is to send bus address line A13 to the 'device selector' circuitry, along with A14-A17, in the MM11-K (it goes to 'Decode X-switches', along with A10-A12, in the MM11-L).
Documentation
MM11-K documentation does not appear to be extant; it is covered in the "PDP-11/05 Technical Manual" (EK-11005-TM-003), Chapter 12, "MM11-K and L Detailed Descriptions"; and the MM11-L documentation is of course largely applicable.
