Question about DEC PMI Processors & Gear Acquisition

My reference for PMI memory placement. -------------------------------------------------------------------------------- Note 28.0 MSV11-Q/M/J Memory Comparisons No replies FURILO::GIORGETTI 175 lines 21-AUG-1985 23:07 -------------------------------------------------------------------------------- +---------------+ +-----------------+ | d i g i t a l | | uNOTE # 028 | +---------------+ +-----------------+ +----------------------------------------------------+-----------------+ | Title: MSV11-Q/M/J MEMORY COMPARISONS | Date: 28-JUN-85 | +----------------------------------------------------+-----------------+ | Originator: JACK TOTO | Page 1 of 3 | +----------------------------------------------------+-----------------+ This MicroNote will compare three of Digital Equipment Corporation's newest memory modules. Following the description of each memory module, is a chart which, list the differences between these memories. MSV11-Q ------- The MSV11-Q has three versions, the MSV11-QA, the MSV11-QB and the MSV11-QC. The MSV11-QA (M7551-A) is a quad size Q-bus memory module and contains 1MB of MOS RAM using 64K bit parts. The MSV11-QA has two etch revisions which must be checked when configuring the module into a system. The two revisions are the C rev and the A rev, both of these revisions are discussed in the Users Guide (EK-MSV1Q-UG) and in Micronote # 030. The second version of the MSV11-Q is the MSV11-QB (M7551-B) which is a half populated quad size Q-bus memory module containing 2MB of MOS RAM using 256K bit parts. The last version of the MSV11-Q is the MSV11-QC which is a fully populated MSV11-QB quad size Q-bus memory module containing 4MB of MOS RAM using 256K bit parts. Both the MSV11-QB and the MSV11-QC use the MSV11-QA printed circuit board, however that board is ECOed to etch level C. MSV11-J ------- The MSV11-J has four versions, the MSV11-JB and MSV11-JC which are used in the PDP-11/84 UNIBUS systems and the MSV11-JD and MSV11-JE are used in either the MicroPDP-11/83 Q-bus systems, or the PDP-11/84 UNIBUS systems. All four modules use ECC memory for error correction, as well as using 256K bit MOS RAM parts on either a half or fully populated quad size module. NOTE: ----- NONE OF THE FOUR MSV11-J MODULES CAN BE PLACED IN A Q/Q BACKPLANE SLOT. IF THIS IS ATTEMPTED PERMANENT DAMAGE WILL BE DONE TO THE BOARDS AND TO THE SYSTEM. The MSV11-JB (M8637-BA) is a half populated quad size PMI memory module containing 1MB of memory. The second version of the MSV11-J is the MSV11-JC (M8639-CA), this is a fully populated MSV11-JB quad size PMI memory module containing 2MB of memory. These two modules can not be used in a Q-bus system due to gate array incompatibilities, and can only 217 uNOTE # 028 Page 2 of 3 be used in PDP-11/84 systems which use the UNIBUS/PMI bus interface (KTJ11-A). The third version of the MSV11-J is the MSV11-JD (M8639-DA) which is a half populated quad size PMI memory module containing 1MB of memory. The last version of the MSV11-J is the MSV11-JE, (M8639-EA) which is a fully populated MSV11-JD quad size PMI memory module containing 2MB of memory. These last two modules can be used with either the MicroPDP-11/83 system which uses the Q-bus/PMI bus interface or the PDP-11/84 system which was mentioned above. For details reference the PMI protocol Micronote # xxx. Although the MSV11-JD and MSV11-JE are PMI memories they can be used in two other Q-bus configurations. 1. If either of these two memories are used in slots 1 and/or 2 of a Q/CD backplane such as the H9276 (BA11-S box) or in the MicroPDP-11 BA23 backplane, and with the standard 15MHZ KDJ11-B cpu (non-fpj compatible) in slot 3, the system will perform PMI memory cycles. In the case of BA23 backplanes, a maximum of two memory modules may be used in slots ahead of the processor, with a minimum of one memory module in front of the processor still functioning as PMI memory. In the case of the H9276 backplane a number of MSV11-JD/JE memory modules may be used ahead of the processor bringing the system to a full 4MB of PMI memory. 2. If in a Q/CD or BA23 backplane the memories reside in slots 2&3 with either of the KDF11 or KDJ11 processors in the slot 1 the MSV11-J memories will respond as standard Q-bus memories, performing normal Q-bus and block mode memory cycles. This use of the MSV11-J memories is also true for the MicroVAX cpu. However the fact that the MicroVAX I cpu is a two board set requires a slightly different configuration. Slots 1&2 will be used for the MicroVAX I cpu boards with only one memory card used, that being located in slot 3 for the BA23 backplane and one or more memory cards being used for other Q/CD backplanes. The only constraint with either of the second configurations is that in the BA23 or other Q/CD backplanes no module may be placed adjacent to the MSV11-J that uses pins in the CD connector. Instead leave an empty slot between the MSV11-J and this option. An option which does not use the CD interconnect may be placed adjacent to the MSV11-J.