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Note 28.0                MSV11-Q/M/J Memory Comparisons               No replies
FURILO::GIORGETTI                                   175 lines  21-AUG-1985 23:07
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      +---------------+                                    +-----------------+
      | 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

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      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. 


      MSV11-M
      -------
      The MSV11-M has two  versions;  the  MSV11-MA  and  the  MSV11-MB.   The
      MSV11-MA  (M7506-AA)  is a half populated dual sized Q-bus memory module
      which contains 0.5MB of MOS RAM using 256K parts.   The  second  version
      the  MSV11-MB  (M7506-BA)  is  a  fully populated dual size Q-bus memory
      module containing 1MB of MOS RAM using 256K parts.





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                                                           uNOTE # 028
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                             MEMORY COMPARISON TABLE
                             -----------------------
      +-----------------------------------------------------------------------+
      |ATTRIBUTE     | MSV11-QA/QB/QC     |   MSV11-MA/MB  | MSV11-JB/JC/JD/JE|
      +--------------+--------------------+----------------+------------------+
      |MEMORY SIZE   | 1MB, 2MB, 4MB      |   0.5MB, 1MB   |   1MB, 2MB       |
      +--------------+--------------------+----------------+------------------+
      |FORM FACTOR   |   QUAD             |    DUAL        |    QUAD          |
      +--------------+--------------------+----------------+------------------+
      |SYSTEM SIZE   |   Q18/Q22          |    Q18/Q22     |   PMI/CD  ONLY   |
      +--------------+--------------------+----------------+------------------+
      |BLOCK MODE    |   YES              |    YES         | YES  (JD/JE ONLY)|
      +--------------+--------------------+----------------+------------------+
      |BLOCK MODE    |   YES FOR REV-A    |       NO       |       NO         |
      |CONFIGURABLE  |   NO FOR REV-C     |(DEFAULT OPTION)| (DEFAULT OPTION) |
      +--------------+--------------------+----------------+------------------+
      |AC BUS LOADS  |   2.4              |    2.0         |    2.5           |
      +--------------+--------------------+----------------+------------------+
      |DC BUS LOADS  |   1.0              |    1.0         |    0.5           |
      +--------------+--------------------+----------------+------------------+
      |AMPS @ +5 VDC |      TYP    MAX    |     TYP   MAX  |        TYP  MAX  |
      |              | QA   2.4    3.99   | MA  2.19  3.11 | JB/JD  1.5  3.94 |
      |(ACTIVE ONLY) | QB   2.3    3.59   | MB  2.22  3.34 | JC/JE  1.7  4.29 |
      |              | QC   2.5    4.30   |                |                  |
      +--------------+--------------------+----------------+------------------+
      |AMPS @ +12VDC |            NO +12V SUPPLY  NEEDED                      |
      +--------------+--------------------+----------------+------------------+
      |WATTS         |      TYP    MAX    |     TYP   MAX  |        TYP  MAX  |
      |              | QA   12.0   20.95  | MA  11.0  16.3 | JB/JD  7.5  19.7 |
      |(ACTIVE ONLY) | QB   11.5   18.85  | MB  11.1  17.5 | JC/JE  8.5  21.5 |
      |              | QC   12.5   22.58  |                                   |
      +--------------+--------------------+----------------+------------------+
      |MEMORY ERROR  |   PARITY           |     PARITY     |     ECC          |
      |CORERECTION   |                    |                |                  |
      +--------------+--------------------+----------------+------------------+
      |BATTERY BACKUP| YES FOR REV-C      |     YES        |     YES          |
      |SUPPORT       | NO FOR REV-A       |                |                  |
      +--------------+--------------------+----------------+------------------+
      |DIAGNOSTICS   |CVMSAA FOR PDP11s   |     SAME       |     CVMJA0       |
      |              |EHXMS FOR MICROVAX  |     SAME       |                  |
      +--------------+--------------------+----------------+------------------+
      |MAINTENANCE   |     MP01931        |     MP02053    |     MP02056      |
      |PRINTSET      |                    |                |                  |
      +--------------+--------------------+----------------+------------------+
      |USER GUIDE    |  EK-MSV1Q-UG       | EK-MSV1M-UG    | EK-MSV1J-UG      |
      +--------------+--------------------+----------------+------------------+





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