PDP-8 Memory Module Maps
Part of
the PDP-8 Hardware Documentation
|
Note: The following material has been proofread a few times, but the DEC original drawings from which this material is taken were not printed clearly, and as a result, there may be errors here! I would like to thank Kevin Murrell for his work on this.
Note, to make this figure easier to type, I've turned it on its side!
Key: ---- unused slot ++ low half of double height module * used only with #183 memory extension control ^ used only with #188 memory parity option ~ Component plate containing inhibit driver resistors = Memory Stack Front end of Memory Backplane Top Bottom MA MB MC MD ME MF 1 ~ ~ R203 * R205 * R201 * R111 * 2 ~ ~ R203 * R205 * R201 * R002 * 3 ~ ~ R151 * R201 * R201 * R111 * 4 ~ ~ R151 * R201 * R603 * R002 * 5 ~ ~ R151 * R201 * R603 * W640 * 6 ~ ~ G209 ++ R111 * R123 * 7 ~ ~ G209 ++ R107 * R123 * 8 = = G209 ++ R107 * B360 ^ 9 = = G209 ++ R002 ^ B104 ^ 10 = = W025 ++ R111 ^ R603 ^ 11 = = W025 ++ B130 ^ R202 ^ 12 = = G209 ++ B130 ^ B130 ^ 13 = = G209 ++ B130 ^ B130 ^ 14 = = G209 ++ B130 ^ R202 15 = = G209 ++ R405 R202 16 = = R650 B204 R111 R202 17 = = W300 ++ R002 R603 18 = = W300 ++ R111 R603 19 = = W607 B104 R107 R202 20 = = B602 B360 R202 R202 21 = = G208 G208 R203 R603 22 = = G208 G208 R220 R220 23 = = W025 ++ R220 R220 24 = = G208 G208 R220 R220 25 G007 G007 G208 ^ R650 R205 W050 26 G007 G007 R650 R650 R650 R650 27 G007 G007 R650 R650 R650 R650 28 G007 G007 R650 R650 R650 R650 29 G007 G007 R650 R650 ---- ---- 30 G007 G007 ---- W640 W011 * W070 31 G007 ^ G008 W640 B684 * W011 * W011 * 32 R603 * B684 * B684 * B684 * W011 * W011 * 33 R603 * B684 * B684 * B684 * W011 * W011 * 34 R603 * B684 * B684 * B684 * W011 W011 35 W026 B684 * B684 * W024 * W011 W011 36 W024 W024 W024 W024 W024 W024 MA MB MC MD ME MF Top Bottom Back end of Memory Backplane