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https://github.com/nathanriggs/AppleIIAsm-Collection.git
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9849dbb5ea
items in disk folder will be updated automatically, whereas items in the source folder will be updated periodically due to having to manually sort through files to copy and paste
781 lines
20 KiB
Plaintext
781 lines
20 KiB
Plaintext
JMP COMMONX
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*
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*-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=*
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* *
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* COMMON.LIB *
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* *
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* AUTHOR: NATHAN RIGGS *
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* CONTACT: NATHAN.RIGGS@ *
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* OUTLOOK.COM *
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* *
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* VERSION: 0.1.2 *
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* DATE: 30-OCT-2018 *
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* ASSEMBLER: MERLIN 8 PRO *
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* *
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* LICENSE: APACHE 2.0 LICENSE *
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* WHEN APPLICABLE. CODE *
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* INSPIRED BY THE WORKS OF *
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* OTHERS MAY FALL UNDER A *
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* DIFFERENT LICENSE. *
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* *
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* COMMON ASM ROUTINES *
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* LIBRARY FOR FUNCTIONS SUCH *
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* AS MEMORY SWAPPING. *
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* *
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*------------------------------*
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* *
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* LIST OF ROUTINES *
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* *
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* MEMFILL : FILL LOCATION WITH *
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* A SINGLE VALUE. *
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* *
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* MEMMOVE : MOVE A BLOCK OF *
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* MEMORY FROM ONE *
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* LOC TO ANOTHER. *
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* *
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* DELAYMS : DELAY FOR A NUMBER *
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* OF MILLISECONDS. *
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* THIS DEPENDS ON *
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* THE ACTUAL SYSTEM *
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* BEING USED, SO *
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* ISN'T AS EASILY *
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* PORTED TO OTHER *
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* 6502 SIBLINGS. *
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* *
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* ZSAVE : SAVE STATE OF FREE *
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* ZERO PAGE LOCATIONS *
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* AT MEM LOC SPECIFIED *
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* *
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* ZLOAD : LOAD PREVIOUS SAVED *
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* ZERO PAGE VALUES *
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* BACK INTO PROPER *
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* LOCATION. *
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* *
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*-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=*
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*
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*``````````````````````````````*
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* MEMFILL :: FILL MEMORY LOC *
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*- -*
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* FILLS A BLOCK OF MEMORY WITH *
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* THE SPECIFIED VALUE; USED *
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* OFTEN TO CLEAR LARGE BLOCKS. *
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*- -*
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* CLOBBERS: *
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* *
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* FLAGS: ????---- REG: AXYM *
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*- -*
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* CYCLES: ??? *
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* SIZE: *
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*- -*
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* USAGE: *
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* *
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* LDA #>$6A00 *
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* PHA *
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* LDA #<$6A00 *
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* PHA *
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* LDA #>1024 *
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* PHA *
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* LDA #<1024 *
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* PHA *
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* LDA #0 *
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* PHA *
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* JSR MEMFILL *
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*- -*
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* ENTRY *
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* *
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* TOP OF STACK *
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* *
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* LOW BYTE OF RETURN ADDRESS *
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* HI BYTE OF RETURN ADDRESS *
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* FILL VALUE FOR MEMORY *
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* ARRAY SIZE *
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* LOW BYTE OF STARTING POINT *
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* HIGH BYTE OF STARTING POINT *
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*- -*
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* EXIT *
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* *
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* TOP OF STACK *
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* *
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* LOW BYTE OF RETURN ADDRESS *
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* HI BYTE OF RETURN ADDRESS *
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* *
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* Y = COUNTER; TRASH *
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* X = COUNTER; TRASH *
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* A = LOW BYTE OF RET ADDR *
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*- -*
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* ADAPTED FROM LEVANTHAL AND *
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* WINTHROP'S /6502 ASSEMBLY *
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* LANGUAGE ROUTINES/. *
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* AS SUCH, THIS MAY NOT FALL *
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* UNDER THE APACHE 2.0 LICENSE *
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* AGREEMENT, SINCE THE BOOK *
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* WAS WRITTEN BEFORE THE *
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* LICENSE! *
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* *
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* THAT SAID, LEVENTHAL WROTE *
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* THAT THE PURPOSE OF THE BOOK *
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* WAS TO COPY THE SOURCE CODE, *
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* AS REINVENTING THE WHEEL IS *
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* TEDIOUS, AND HE PLACED NO *
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* RESTRICTIONS ON ITS USE. *
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*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
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*
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MEMFILL
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*
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** SAVE RETURN ADDRESS
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*
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PLA
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STA :RETADR
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PLA
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STA :RETADR+1
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*
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** GET PARAMETERS
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*
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PLA
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STA :VALUE
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PLA
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STA :ARYSZ
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PLA
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STA :ARYSZ+1
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PLA
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STA ADDR1 ; ZERO PAGE POINTER
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PLA ; DEFINED IN
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STA ADDR1+1 ; DECS
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*
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** FILL WHOLE PAGES FIRST
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*
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LDA :VALUE ; GET VAL FOR FILL
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LDX :ARYSZ+1 ; X=# OF PAGES TO DO
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BEQ :PARTPG ; BRANCH IF HIGHBYTE OF SZ = 0
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LDY #0
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:FULLPG
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STA (ADDR1),Y
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INY ; INC TO NEXT BYTE
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BNE :FULLPG ; BRANCH IF NOT DONE W/ PAGE
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INC ADDR1+1 ; ADVANCE TO NEXT PAGE
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DEX
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BNE :FULLPG ; BRANCH IF NOT DONE W/ PAGES
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*
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** DO THE REMAINING PARTIAL PAGE
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** REGISTER A STILL CONTAINS VALUE
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*
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:PARTPG
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LDX :ARYSZ ;GET # OF BYTES IN FINAL PAGE
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BEQ :EXIT ; BRANCH IF LOW BYTE = 0
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LDY #0
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:PARTLP
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STA (ADDR1),Y ; STORE VAL
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INY ; INCREMENT INDEX
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DEX ; DECREMENT COUNTER
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BNE :PARTLP ; BRANCH IF NOT DONE
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:EXIT
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*
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** RESTORE RETURN ADDRESS
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*
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LDA :RETADR+1
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PHA
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LDA :RETADR
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PHA
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RTS
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*
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** DATA
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*
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:VALUE DS 1 ; FILL VALUE
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:ARYSZ DS 2 ; ARRAY SIZE
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:RETADR DS 2
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*
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*``````````````````````````````*
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* MEMMOVE :: MOVE MEM BLOCK *
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*- -*
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* MOVES A SPECIFIED BLOCK OF *
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* MEMORY FROM A SOURCE ADDRESS *
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* TO A DESTINATION ADDRESS *
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* RANGE. *
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*- -*
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* CLOBBERS: *
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* *
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* FLAGS: ????---- REG: AXYM *
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*- -*
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* CYCLES: ??? *
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* SIZE: *
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*- -*
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* USAGE: *
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* *
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* LDA #>$6A00 *
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* PHA *
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* LDA #<$6A00 *
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* PHA *
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* LDA #>$7000 ; DEST *
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* PHA *
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* LDA #<$7000 *
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* PHA *
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* LDA #>1024 *
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* PHA *
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* LDA #<1024 *
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* PHA *
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* JSR MEMMOVE *
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*- -*
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* ENTRY *
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* *
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* TOP OF STACK *
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* *
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* LOW BYTE OF RETURN ADDRESS *
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* HI BYTE OF RETURN ADDRESS *
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* NUMBER OF BYTES TO MOVE *
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* LOW BYTE OF DESTINATION *
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* HIGH BYTE OF DESTINATION *
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* LOW BYTE OF SOURCE ADDRESS *
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* HIGH BYTE OF SOURCE ADDRESS *
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*- -*
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* EXIT *
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* *
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* TOP OF STACK *
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* *
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* LOW BYTE OF RETURN ADDRESS *
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* HI BYTE OF RETURN ADDRESS *
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* *
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* Y = COUNTER; TRASH *
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* X = COUNTER; TRASH *
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* A = LOW BYTE OF RET ADDR *
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*- -*
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* ADAPTED FROM LEVANTHAL AND *
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* WINTHROP'S /6502 ASSEMBLY *
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* LANGUAGE ROUTINES/. *
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* AS SUCH, THIS MAY NOT FALL *
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* UNDER THE APACHE 2.0 LICENSE *
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* AGREEMENT, SINCE THE BOOK *
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* WAS WRITTEN BEFORE THE *
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* LICENSE! *
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* *
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* THAT SAID, LEVENTHAL WROTE *
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* THAT THE PURPOSE OF THE BOOK *
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* WAS TO COPY THE SOURCE CODE, *
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* AS REINVENTING THE WHEEL IS *
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* TEDIOUS, AND HE PLACED NO *
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* RESTRICTIONS ON ITS USE. *
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*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
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*
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MEMMOVE
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*
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*
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** SAVE RETURN ADDRESS
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*
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PLA
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STA :RETADR
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PLA
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STA :RETADR+1
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*
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** GET PARAMETERS
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*
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PLA
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STA :MVELEN
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PLA
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STA :MVELEN+1
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PLA
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STA ADDR2 ; ZERO PAGE POINTER
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PLA
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STA ADDR2+1
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PLA
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STA ADDR1
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PLA
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STA ADDR1+1
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*
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** DETERMINE IF DEST AREA IS
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** ABOVE SRC AREA BUT OVERLAPS
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** IT. REMEMBER, OVERLAP CAN BE
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** MOD 64K. OVERLAP OCCURS IF
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** STARTING DEST ADDRESS MINUS
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** STARTING SRC ADDRESS (MOD
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** 64K) IS LESS THAN NUMBER
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** OF BYTES TO MOVE.
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*
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LDA ADDR2 ;CALC DEST-SRC
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SEC
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SBC ADDR1
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TAX
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LDA ADDR2+1
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SBC ADDR1+1 ; MOD 64K AUTOMATIC
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; -- DISCARD CARRY
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TAY
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TXA ; CMP WITH # OF BYTES TO MOVE
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CMP :MVELEN
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TYA
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SBC :MVELEN+1
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BCS :DOLEFT ; BRANCH IF NO OVERLAP
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*
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** DEST AREA IS ABOVE SRC AREA
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** BUT OVERLAPS IT.
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** MOVE FROM HIGHEST ADDR TO
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** AVOID DESTROYING DATA
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*
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JSR :MVERHT
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JMP :EXIT
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*
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** NO PROB DOING ORDINARY MOVE
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** STARTING AT LOWEST ADDR
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*
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:DOLEFT
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JSR :MVELEFT
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:EXIT
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JMP :MREXIT
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*
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********************************
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* SUBROUTINE: MVELEFT *
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********************************
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*
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:MVELEFT
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LDY #0 ; ZERO INDEX
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LDX :MVELEN+1 ; X=# OF FULL PP TO MOVE
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BEQ :MLPART ; IF X=0, DO PARTIAL PAGE
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:MLPAGE
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LDA (ADDR1),Y
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STA (ADDR2),Y ;MOVE ONE BYTE
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INY ; NEXT BYTE
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BNE :MLPAGE ; CONT UNTIL 256B MOVED
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INC ADDR1+1 ; ADV TO NEXT SRC PAGE
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INC ADDR2+1 ; ADV NEXT DEST PAGE
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DEX ; DEC PAGE COUNT
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BNE :MLPAGE ; CONT UNTIL ALL FULL
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; PAGES ARE MOVED
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:MLPART
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LDX :MVELEN ; GET LENGTH OF LAST PAGE
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BEQ :MLEXIT ; BR IF LENGTH OF LAST
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; PAGE = 0
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; REG Y IS 0
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:MLLAST
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LDA (ADDR1),Y
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STA (ADDR2),Y ; MOVE BYTE
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INY ; NEXT BYTE
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DEX ; DEC COUNTER
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BNE :MLLAST ; CONT UNTIL LAST P DONE
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:MLEXIT
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JMP :MREXIT
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*
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********************************
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* SUBROUTINE: MVERHT *
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********************************
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*
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:MVERHT
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*
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** MOVE THE PARTIAL PAGE FIRST
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*
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LDA :MVELEN+1
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CLC
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ADC ADDR1+1
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STA ADDR1+1 ;POINT TO LAST P OF SRC
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LDA :MVELEN+1
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CLC
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ADC ADDR2+1
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STA ADDR2+1 ; POINT TO LAST P OF DEST
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*
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** MOVE THE LAST PARTIAL PAGE FIRST
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*
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LDY :MVELEN ;GET LENGTH OF LAST PAGE
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BEQ :MRPAGE ; IF Y=0 DO THE FULL PAGES
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:MR0
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DEY ; BACK UP Y TO NEXT BYTE
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LDA (ADDR1),Y
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STA (ADDR2),Y ; MOVE BYTE
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CPY #0
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BNE :MR0 ; BR IF NOT DONE W LAST P
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:MRPAGE
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LDX :MVELEN+1 ; GET BYTE OF COUNT AS P CT
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BEQ :MREXIT ; BR IF HYBYTE = 0 (NO FULL P)
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:MR1
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DEC ADDR1+1 ; BACK UP TO PREV SRC PAGE
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DEC ADDR2+1 ; AND DEST
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:MR2
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DEY ; BACK UP Y TO NEXT BYTE
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LDA (ADDR1),Y
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STA (ADDR2),Y ; MOVE BYTE
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CPY #0
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BNE :MR2 ; BR IF NOT DONE W THIS PAGE
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DEX
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BNE :MR1 BR IF NOT ALL PAGES MOVED
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:MREXIT
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*
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** RESTORE RETURN ADDRESS
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*
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LDA :RETADR+1
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PHA
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LDA :RETADR
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PHA
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RTS
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*
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** DATA
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*
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:RETADR DS 2
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:MVELEN DS 2
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*
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*``````````````````````````````*
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* DELAYMS :: DELAY X MILLISECS *
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*- -*
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* DELAYS FOR X NUMBER OF *
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* MILLISECONDS BY LOOPING *
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* THROUGH PRECISELY CALCULATED *
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* NUMBER OF CYCLES. *
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*- -*
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* CLOBBERS: *
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* *
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* FLAGS: ????---- REG: -XY- *
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*- -*
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* CYCLES: ??? *
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* SIZE: *
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*- -*
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* USAGE: *
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* *
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* LDY #250 ;1/4 SEC *
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* JSR DELAYMS *
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*- -*
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* ENTRY *
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* *
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* Y = NUMBER OF MILLISECONDS *
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*- -*
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* EXIT *
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* *
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* Y = COUNTER; TRASH *
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* X = COUNTER; TRASH *
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* A = UNCHANGED *
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*- -*
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* ADAPTED FROM LEVANTHAL AND *
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* WINTHROP'S /6502 ASSEMBLY *
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|
* LANGUAGE ROUTINES/. *
|
|
* AS SUCH, THIS MAY NOT FALL *
|
|
* UNDER THE APACHE 2.0 LICENSE *
|
|
* AGREEMENT, SINCE THE BOOK *
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|
* WAS WRITTEN BEFORE THE *
|
|
* LICENSE! *
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|
* *
|
|
* THAT SAID, LEVENTHAL WROTE *
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|
* THAT THE PURPOSE OF THE BOOK *
|
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* WAS TO COPY THE SOURCE CODE, *
|
|
* AS REINVENTING THE WHEEL IS *
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|
* TEDIOUS, AND HE PLACED NO *
|
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* RESTRICTIONS ON ITS USE. *
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|
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
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*
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DELAYMS
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*
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MSCNT EQU $0CA ; 202 TIMES THROUGH DELAY1
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; SPECIFIC TO 1.23 MHZ
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; SPEED OF APPLE II
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:DELAY
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CPY #0 ; 2 CYCLES
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BEQ :EXIT ; 2C (EXIT IF DEL=0)
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NOP ; 2 CYCLES (MAKE OVERHEAD=25C)
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*
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** IF DELAY IS 1MS THEN GOTO LAST1
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** THIS LOGIC IS DESIGNED TO BE
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** 5 CYCLES THROUGH EITHER ATH
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*
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CPY #1 ; 2 CYCLES
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BNE :DELAYA ; 3C IF TAKEN, ELSE 2C
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JMP :LAST1 ; 3C
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*
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** DELAY 1 MILLISENCOND TIMES (Y-1)
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*
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:DELAYA
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DEY ; 2C (PREDEC Y)
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:DELAY0
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LDX #MSCNT ; 2C
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:DELAY1
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DEX ; 2C
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BNE :DELAY1 ; 3C
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NOP ; 2C
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NOP ; 2C
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DEY ; 2C
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BNE :DELAY0 ; 3C
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:LAST1
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*
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** DELAY THE LAST TIME 25 CYCLES
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** LESS TO TAKE THE CALL, RETURN,
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** AND ROUTINE OVERHEAD INTO
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** ACCOUNT.
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*
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LDX #MSCNT-3 ; 2C
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:DELAY2
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DEX ; 2C
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BNE :DELAY2 ; 3C
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:EXIT
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RTS ; 6C
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*
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*
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*``````````````````````````````*
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* ZSAVE :: SAVE 0-PAGE FREE *
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*- -*
|
|
* STORES THE VALUES IN THE *
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* LITTLE FREE SPACE ON THE *
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* ZERO PAGE AT AN ALTERNATE *
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* MEMORY LOCATION TO BE *
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* RETRIEVED AND RESTORED AT A *
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* LATER POINT. *
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*- -*
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* CLOBBERS: *
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* *
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* FLAGS: ????---- REG: AXYM *
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*- -*
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* CYCLES: ??? *
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* SIZE: *
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*- -*
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|
* USAGE: *
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* *
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* LDA #>$6A00 *
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* PHA *
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* LDA #<$6A00 *
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* PHA *
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* JSR ZSAVE *
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*- -*
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* ENTRY *
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* *
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* TOP OF STACK *
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* *
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* LOW BYTE OF RETURN ADDRESS *
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* HI BYTE OF RETURN ADDRESS *
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* LOW BYTE OF DESTINATION *
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* HIGH BYTE OF DESTINATION *
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*- -*
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* EXIT *
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* *
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* TOP OF STACK *
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* *
|
|
* LOW BYTE OF RETURN ADDRESS *
|
|
* HI BYTE OF RETURN ADDRESS *
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|
* *
|
|
* Y = TRASH *
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|
* X = TRASH *
|
|
* A = LOW BYTE OF RET ADDR *
|
|
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
|
|
*
|
|
ZSAVE
|
|
*
|
|
** LOAD ADDR1 ZERO PAGE AREA FIRST,
|
|
** SINCE WE'LL BE USING THAT
|
|
*
|
|
** NOTE THAT THIS SHOULD ALWAYS BE
|
|
** $06 AND $07, OR ELSE CODE WILL
|
|
** HAVE TO CHANGE.
|
|
*
|
|
LDX ADDR1
|
|
LDY ADDR1+1
|
|
*
|
|
** SAVE RETURN ADDRESS
|
|
*
|
|
PLA
|
|
STA :RETADR
|
|
PLA
|
|
STA :RETADR+1
|
|
*
|
|
** GET PARAMETERS
|
|
*
|
|
PLA
|
|
STA ADDR1
|
|
PLA
|
|
STA ADDR1+1
|
|
*
|
|
** COPY ZERO PAGE TO SPECIFIED
|
|
** NON-ZERO LOCATION (ONLY THE
|
|
** FREE ONES..)
|
|
*
|
|
TYA ; STORE ADDR1 VALS
|
|
LDY #1 ; FIRST
|
|
STA (ADDR1),Y
|
|
LDY #0
|
|
TXA
|
|
STA (ADDR1),Y
|
|
LDY #2
|
|
LDA $08
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA $09
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA $19
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA $1E
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA $E3
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA $EB
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA $EC
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA $ED
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA $EE
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA $EF
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA $FA
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA $FB
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA $FC
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA $FD
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA $FE
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA $FF
|
|
STA (ADDR1),Y
|
|
*
|
|
** RESTORE RETURN ADDRESS
|
|
*
|
|
LDA :RETADR+1
|
|
PHA
|
|
LDA :RETADR
|
|
PHA
|
|
*
|
|
RTS
|
|
*
|
|
** DATA
|
|
*
|
|
:RETADR DS 2
|
|
*
|
|
*``````````````````````````````*
|
|
* ZLOAD :: RESTORE 0-PAGE FREE *
|
|
*- -*
|
|
* RESTORES PREVIOUSLY SAVED *
|
|
* ZERO PAGE VALUES FROM *
|
|
* HIGHER MEMORY LOCATION. *
|
|
* CLOBBERS: *
|
|
* *
|
|
* FLAGS: ????---- REG: AXYM *
|
|
*- -*
|
|
* CYCLES: ??? *
|
|
* SIZE: *
|
|
*- -*
|
|
* USAGE: *
|
|
* *
|
|
* LDA #>$6A00 *
|
|
* PHA *
|
|
* LDA #<$6A00 *
|
|
* PHA *
|
|
* JSR ZLOAD *
|
|
*- -*
|
|
* ENTRY *
|
|
* *
|
|
* TOP OF STACK *
|
|
* *
|
|
* LOW BYTE OF RETURN ADDRESS *
|
|
* HI BYTE OF RETURN ADDRESS *
|
|
* LOW BYTE OF SOURCE *
|
|
* HIGH BYTE OF SOURCE *
|
|
*- -*
|
|
* EXIT *
|
|
* *
|
|
* TOP OF STACK *
|
|
* *
|
|
* LOW BYTE OF RETURN ADDRESS *
|
|
* HI BYTE OF RETURN ADDRESS *
|
|
* *
|
|
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
|
|
*
|
|
ZLOAD
|
|
*
|
|
** SAVE RETURN ADDRESS
|
|
*
|
|
PLA
|
|
STA :RETADR
|
|
PLA
|
|
STA :RETADR+1
|
|
*
|
|
** GET PARAMETERS
|
|
*
|
|
PLA
|
|
STA ADDR1
|
|
PLA
|
|
STA ADDR1+1
|
|
*
|
|
** COPY ZERO PAGE TO SPECIFIED
|
|
** NON-ZERO LOCATION (ONLY THE
|
|
** FREE ONES..)
|
|
*
|
|
LDY #2 ; START 2 AHEAD
|
|
LDA (ADDR1),Y ; AND PUT ADDR1
|
|
STA $08 ; AREA LAST
|
|
INY
|
|
LDA (ADDR1),Y
|
|
STA $09
|
|
INY
|
|
LDA (ADDR1),Y
|
|
STA $19
|
|
INY
|
|
LDA (ADDR1),Y
|
|
STA $1E
|
|
INY
|
|
LDA (ADDR1),Y
|
|
STA $E3
|
|
INY
|
|
LDA (ADDR1),Y
|
|
STA $EB
|
|
INY
|
|
LDA (ADDR1),Y
|
|
STA $EC
|
|
INY
|
|
LDA (ADDR1),Y
|
|
STA $ED
|
|
INY
|
|
LDA (ADDR1),Y
|
|
STA $EE
|
|
INY
|
|
LDA (ADDR1),Y
|
|
STA $EF
|
|
INY
|
|
LDA (ADDR1),Y
|
|
STA $FA
|
|
INY
|
|
LDA (ADDR1),Y
|
|
STA $FB
|
|
INY
|
|
LDA (ADDR1),Y
|
|
STA $FC
|
|
INY
|
|
LDA (ADDR1),Y
|
|
STA $FD
|
|
INY
|
|
LDA (ADDR1),Y
|
|
STA $FE
|
|
INY
|
|
LDA (ADDR1),Y
|
|
STA $FF
|
|
*
|
|
** NOW GET ZERO PAGE VALUES
|
|
** FOR SPACE OCCUPIED BY ADDR; RETURN IN X,Y
|
|
*
|
|
LDY #0
|
|
LDA (ADDR1),Y
|
|
TAX
|
|
LDA (ADDR1+1),Y
|
|
TAY
|
|
STX ADDR1
|
|
STY ADDR1+1
|
|
*
|
|
** RESTORE RETURN ADDRESS
|
|
*
|
|
LDA :RETADR+1
|
|
PHA
|
|
LDA :RETADR
|
|
PHA
|
|
*
|
|
RTS
|
|
*
|
|
** DATA
|
|
*
|
|
:RETADR DS 2
|
|
*
|
|
*
|
|
COMMONX RTS
|