File: RESOVD.MA of Tape: Various/Tests/Blank-Tape-Unit1
(Source file text)
/RESOVD - OVERLAY DRIVER FOR RES
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/COPYRIGHT (C) 1977,1978 BY DIGITAL EQUIPMENT CORPORATION
/ AND 1979 BY DATAPLAN GMBH
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/THE INFORMATION IN THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE
/AND SHOULD NOT BE CONSTRUED AS A COMMITMENT BY DIGITAL EQUIPMENT
/CORPORATION. DIGITAL EQUIPMENT CORPORATION ASSUMES NO RESPONSIBILITY
/FOR ANY ERRORS THAT MAY APPEAR IN THIS DOCUMENT.
/
/THE SOFTWARE DESCRIBED IN THIS DOCUMENT IS FURNISHED TO THE PURCHASER
/UNDER A LICENSE FOR USE ON A SINGLE COMPUTER SYSTEM AND CAN BE COPIED
/(WITH INCLUSION OF DIGITAL'S COPYRIGHT NOTICE) ONLY FOR USE IN SUCH
/SYSTEM, EXCEPT AS MAY OTHERWISE BE PROVIDED IN WRITING BY DIGITAL.
/
/DIGITAL EQUIPMENT CORPORATION ASSUMES NO RESPONSIBILITY FOR THE USE
/OR RELIABILITY OF ITS SOFTWARE ON EQUIPMENT THAT IS NOT SUPPLIED BY
/DIGITAL.
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/OVERLAY DRIVER
/FOR LINKER PROGRAM MODULES
/VERSION=V4A
/THIS SECT IS TWO LOCATIONS AND CONTAINS THE TRANSFER VECTOR TO SWAPER
/AND A FLAG THAT INDICATES WHETHER A JMP (1) OR JMS (0) WAS PERFORMED
/TO THE TRANSFER VECTOR
/ .SECT XFERV,Z
/ 0 /FLAG, 1=JMP, 0=JMS
/ SWAPER /TRANSFER VECTOR TO SWAP ROUTINE
/THIS IS THE MAIN DRIVER SECTION
.RSECT SWAPER
.GLOBAL SWPTAB,TRANVC
.ZTERNAL XFERV
FIELD 1
SWAP, 6401 /VERSION NUMBER
DCA AC /SAVE CALLING AC
RAL
DCA LINK /AND LINK
RDF /GET CALLING DF
TAD (CDF /FORM CDF
SWAP0, JMP ONCE /DO ONCE ONLY CODE - REPLACED BY DCA EXIT
CDF . /CHANGE TO THIS DATA FIELD
TAD I SWAP /GET OVERLAY,LEVEL,FIELD
DCA BINDAT /SAVE
ISZ SWAP /BUMP POINTER
S1600, TAD I SWAP /GET SUBROUTINE ADDRESS
DCA XITLOC /SAVE
TAD BINDAT /FORM CDF TO CALLED SUBROUTINE
AND (7
RAL CLL
RTL
TAD (CDF
DCA SWAP1A /SAVE
TAD SWAP1A /FORM CIF TO CALLED SUBROUTINE
IAC
DCA EXIT+1 /SAVE FOR EXIT
/LOAD OVERLAY OF CALLED SUBROUTINE
LOAD, TAD BINDAT
AND S1600 /EXTRACT LEVEL OF CALLED SUBROUTINE
BSW
CLL RAL /5 RIGHT
DCA PNTR /SAVE
TAD PNTR
TAD (SWPTAB /COMPUTE ENTRY INTO SWAP TABLE
DCA PFLD /POINTS TO FIELD OF OVERLAY
TAD PNTR /COMPUTE ENTRY INTO CURRENT OVERLAY TABLE
RTR CLL
TAD (CURTAB
DCA PNTR
TAD BINDAT /EXTRACT DESIRED OVERLAY NUMBER
AND (171 /REALLY 170 BUT 171=-7607
RAR CLL /THROW AWAY LEAST SIGNIFICANT
RTR CLL /RIGHT 3
CIA /NEGATE
DCA TEMP
TAD TEMP
TAD I PNTR /COMPARE WITH CURRENT OVERLAY NUMBER FOR LEVEL
SNA CLA /SAME?
JMP SWAP1 /YES, NO READING NEEDED
LOAD1, TAD TEMP /NO, SET TO NEW
CIA
DCA I PNTR /OVERLAY NUMBER
TAD I PFLD
DCA BINDAT /SAVE FIELD OF OVERLAY
ISZ PFLD /POINT AT ADDRESS
TAD I PFLD
DCA REDADD /SAVE IN CALL LOCATION
ISZ PFLD /POINT AT RELATIVE BLOCK #
TAD I PFLD
DCA REDBLK /SAVE TEMPORARILY
ISZ PFLD /POINT AT OVERLAY LENGTH
TAD TEMP /TEST OVERLAY NUMBER
SNA CLA /0?
JMP LOAD2 /YES, NO MULTIPLICATION NEEDED
TAD I PFLD /BLOCK NUMBER = (LENGTH OF OVERLAY)
IAC /TIMES (THE NUMBER OF THE OVERLAY)
CLL RAR /CONVERT PAGES TO BLOCKS
DCA REDCNT /SAVE FOR MULTIPLY
TAD REDCNT /MULTIPLY BLOCK LENGTH
ISZ TEMP /BY OVERLAY NUMBER
JMP .-2
LOAD2, TAD REDBLK /PLUS (RELATIVE BLOCK OF LEVEL)
TAD STRBLK /PLUS (STARTING BLOCK OF PROGRAM)
DCA REDBLK /SAVE IN CALL LOCATION
TAD BINDAT /GET FIELD
AND (7 /MASK
CLL RTR
RTR /POSITION
TAD I PFLD /GET LENGTH AGAIN
BSW
DCA REDCNT /FORM CONTROL WORD
CIF 0
JMS I RESHAN /CALL RESIDENT HANDLER TO READ IN OVERLAY
REDCNT, 7756 /FUNCTION CONTROL WORD (POINTS TO MREAD-1 FOR "ONCE"
REDADD, 7747 /BUFFER ADDRESS (POINTS TO SOFSET FOR "ONCE"
REDBLK, 0 /STARTING BLOCK NUMBER
HLT /ERROR RETURN ADDRESS
SWAP1, TAD XFERV /GET JMP-JMS FLAG
SZA CLA /SET?
JMP SWAP2 /YES, EXECUTE A JMP
CLA CLL CMA RTL /-3
TAD SWAP /BACK UP TO CALLER'S PC
DCA SWAP
TAD I SWAP
SWAP1A, 0 /CDF TO CALLED SUBROUTINE
DCA I XITLOC /SAVE IN CALLED SUBROUTINE
ISZ XITLOC /BUMP TRANSFER ADDRESS
CDF .
TAD (ISZ XFERV
DCA I SWAP /SET BACK UP ENTRY IN XFER VECTOR TABLE
SWAP2, DCA XFERV /CLEAR FLAG
TAD LINK /RESTORE LINK AND AC
RAR CLL
TAD AC
EXIT, 0 /SET DF TO CALLING FIELD
0 /SET IF TO CALLED FIELD
JMP I XITLOC /GO TO CALLED SUBROUTINE
/VARIABLE LOCATIONS
/SOME OF THE FOLLOWING LOCATIONS CONTAIN
/ONCE ONLY CODE TO SET UP STARTING BLOCK
/AND CHECK THAT FILE CAME FROM SYS:
CURTAB=. /CURRENT OVERLAY IN LEVEL TABLE (8 ENTRIES)
STRBLK=. /ENTRY 0 IS USED TO HOLD STARTING BLOCK OF FILE
ONCE, DCA EXIT /SAVE CALLING FIELD
/ALSO ENTRY 0
TAD .-1 /SET UP SO WON'T BE EXECUTED AGAIN
/ALSO ENTRY 1
DCA SWAP0
/ALSO ENTRY 2
CDF 0
/ALSO ENTRY 3
TAD I REDADD /GET STARTING BLOCK FROM "SOFSET"
/ALSO ENTRY 4
DCA STRBLK /SAVE
/ALSO ENTRY 5
TAD I REDCNT /GET RESIDENT? ENTRY POINT
/ALSO ENTRY 6
DCA RESHAN /SAVE
/ALSO ENTRY 7
TAD RESHAN /CHECK ENTRY IS RESIDENT
PFLD, /POINTS TO SWPTAB
TAD (-7607
BINDAT, /CONTAINS OVERLAY,LEVEL,FIELD OF DESIRED SUBROUTINE
SZL CLA /RESIDENT ?
XITLOC, /CONTAINS LOCATION TO GO TO IN DESIRED SUBROUTINE
JMP SWAP0+1 /YES, OK
PNTR, /POINTS INTO CURTAB
HLT /NO, ERROR
TEMP, /TEMP STORAGE
JMP .-1 /DON'T ALLOW CONTINUE
RESHAN, 7607 /OR SOME OTHER RESIDENT ENTRY POINT
AC, 0 /SAVED AC
R VECTORS FOR EACH ENTRY POINT
/IN ALL THE OVERLAYS IN ALL THE LEVELS
/ITS SIZE SHOULD BE MODIFIED BY THE USER
/TO FIT THE MAXIMUM NUMBER OF TRANSFER VECTORS NEEDED
/EACH TRANSFER VECTOR OCCUPIES 4 LOCATIONS
/THE TABLE IS INITIALLY SET UP FOR 24(DEC) (30(OCT)) VECTORS
/THE MAXIMUM SIZE THIS TABLE CAN BE IS 3774 (OCT) LOCATIONS FOR
/511 (DEC) (777 (OCT)) VECTORS
/THE FORMAT OF EACH VECTOR ENTRY IS:
/WORD1: ISZ XFERV
/WORD2: JMS I XFERV+1
/WORD3: LEVEL/OVERLAY/FIELD
/WORD4: ADDRESS
TRANVC,
SIZE=24. /MODIFY THIS LINE TO CHANGE THE SIZE OF THE TABLE
/SET FOR 24(DEC)
*SIZE^4+.