PAL16R4
PAT8033          **-1110-**          MK,85-02-11
DS60 RAM REFRESH AND MAPPER WRITE CONTROL

CLK AS' REQ UDS LDS BGA PWC SWC PTE GND
 OE DAS PWL SWR RAS OFF SAS PWH ECK VCC

;EQUATIONS:

IF(VCC) /PWL  =/PWC*/AS'*/DAS*/PTE* BGA*/LDS*/UDS

        /SWR := SWR*/SWC*/SAS*/DAS* OFF* RAS*/AS'*/LDS* BGA +
               /SWR* ECK* OFF* RAS

        /RAS := RAS*/OFF* ECK*/REQ* SAS +
               /RAS*/REQ*/OFF* SAS +
               /RAS* ECK*/OFF* SAS

        /OFF := OFF*/REQ*/SAS* AS'* ECK* BGA +
                OFF*/REQ* SAS* AS'*/ECK* BGA +
               /OFF*/REQ* SAS +
               /OFF*/RAS* SAS +
               /OFF*/AS'* BGA* UDS* LDS* SAS +
               /OFF* ECK* SAS

        /SAS := SAS* OFF* RAS*/AS'*/ECK +
               /SAS*/AS'* OFF* RAS +
               /SAS*/ECK* OFF* RAS

IF(VCC) /PWH  =/PWC*/AS'*/DAS*/UDS +
               /PWC*/AS'*/DAS*/LDS


FUNCTION TABLE:

CLK  OE BGA REQ PTE PWC SWC UDS LDS AS' DAS ECK
SAS OFF RAS SWR PWH PWL

------------------------------
;C B R PPS ULAD  E  SOR  SPP
;LOG E TWW DDSA  C  AFA  WWW
;KEA Q ECC SS'S  K  SFS  RHL
;----------------------------INITIALIZE
 CLH H HHH HHHH  H  XXX  XHH ;1
 CLH H HHH HHHH  L  HXH  HHH
 CLH H HHH HHHH  H  HXH  HHH
 CLH H HHH HHHH  L  HHH  HHH
 CLH H HHH HHHH  H  HHH  HHH
 CLH H HHH HHHH  L  HHH  HHH
;----------------------------PAGE WRITE CMD (TYPE 1)
 CLX H HXH XXXH  H  HHH  HHH
 CLX H HLH LLLH  L  LHH  HHH
 CLX H HLH LLLH  H  LHH  HHH
 CLX H HLH LLLL  L  LHH  HLH ;10
 CLX H HLH LLLL  H  LHH  HLH
 CLX H HXH XXXL  L  LHH  HXH
 CLH H HHH HHHH  H  HHH  HHH
 CLH H HHH HHHH  L  HHH  HHH
;----------------------------PAGE WRITE CMD (TYPE 2)
 CLH H XXH XXXH  H  HHH  HHH
 CLH H LLH LLLH  L  LHH  HHH
 CLH H LLH LLLH  H  LHH  HHH
 CLH H LLH LLLL  L  LHH  HLL
 CLH H LLH LLLL  H  LHH  HLL
 CLH H XXH XXXL  L  LHH  HXX ;20
 CLH H HHH HHHH  H  HHH  HHH
 CLH H HHH HHHH  L  HHH  HHH
;----------------------------SEGMENT WRITE CMD
 CLH H HHX XXXH  H  HHH  HHH
 CLH H HHL LLLH  L  LHH  HHH
 CLH H HHL LLLH  H  LHH  HHH
 CLH H HHL LLLL  L  LHH  LHH
 CLH H HHL LLLL  H  LHH  LHH
 CLH H HHX XXXL  L  LHH  HHH
 CLH H HHH HHHH  H  HHH  HHH
 CLH H HHH HHHH  L  HHH  HHH ;30
;----------------------------REFRESH SEQUENCES
 CLH L HHH HHHH  H  HHH  HHH
 CLH L HHH HHHH  L  HLH  HHH
 CLH L HHH XXXH  H  HLL  HHH
 CLH L HHH LLLH  L  HLL  HHH
 CLH H HHH LLLH  H  HLL  HHH
 CLH H HHH LLLH  L  HLH  HHH
 CLH H HHH LLLH  H  HLH  HHH
 CLH H HHH LLLH  L  HHH  HHH
 CLH L HHH LLLH  H  HHH  HHH
 CLH L HHH LLLH  L  LHH  HHH ;40
 CLH L HHH LLLH  H  LHH  HHH
 CLH L HHH XXXL  L  LHH  HHH
 CLH L HHH HHHH  H  HLH  HHH
 CLH L HHH HHHH  L  HLH  HHH
 CLH L HHH HHHH  H  HLL  HHH
 CLH L HHH HHHH  L  HLL  HHH
 CLH H HHH HHXH  H  HLL  HHH
 CLH H HHH HHLH  L  HLH  HHH
 CLH H HHH HHLH  H  HLH  HHH
 CLH H HHH HHLH  L  HLH  HHH ;50
 CLH H HHH XXLH  H  HLH  HHH
 CLH H HHH LLLH  L  HHH  HHH
 CLH H HHH LLLH  H  HHH  HHH
 CLH H HHH LLLH  L  LHH  HHH
 CLH H HHH LLLH  H  LHH  HHH
 CLH H HHH XXXL  L  LHH  HHH
 CLH H HHH HHHH  H  HHH  HHH
 CLL L HHH HHHH  L  HHH  HHH
 CLL L HHH HHHH  H  HHH  HHH
-----------------------------


A RAM REFRESH CYCLE PROVIDES "OFF"(CPU ADDRESS STROBE OFF)
AND "RAS" PULSES UPON REQUEST INPUT. THIS SEQUENCE IS
SYNCRONIZED WITH CPU ACTIVITY INDICATED BY ADDRESS STROBE
"AS'". SYNCRONIZED ADDRESS STROBE "SAS" IS USED BY ANOTHER
CIRCUITS IN ORDER TO EXTEND CPU CYCLE IN CASE OF CONFLICT
BEETWEN CPU OR DMA AND REFRESH.
MAPPER WRITE OUTPUTS SYNCRONIZE WRITE CONTROLS AND PROVIDE
ACCESS PROTECTION.

INPUT SIGNALS:

AS' - CPU OR DMA ADDRESS STROBE         ACTIVE LOW
REQ - REFRESH REQUEST                      "    "
UDS - UPPER DATA STROBE                    "    "
LDS - LOW    "      "                      "    "
BGA - DMA CYCLE                            "    "
PWC - PAGE TABLE WRITE COMMAND             "    "
SWC - SEGMENT TABLE WRITE COMMAND          "    "
PTE - PAGE TABLE TRANSCEIVER ENABLED       "    "
DAS - DELAYED ADDRESS STROBE               "    "
ECK - EARLY CLOCK

OUTPUT SIGNALS:

PWL - PAGE WRITE LOWER PART                "    "
SWR - SEGMENT TABLE WRITE                  "    "
RAS - REFRESH RAS STROBE                   "    "
OFF - CPU ADDRESS OFF                      "    "
SAS - SYNCRONIZED ADDRESS STROBE           "    "
PWH - PAGE WRITE HIGH PART                 "    "