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more.sc.s
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more.sc.s
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********************************
* *
* MORE - UN*X MORE COMMAND *
* ASSEMBLES WITH S-C *
* *
********************************
* Memory Map
*
* $0000 - $00FF Zero Page
* $0100 - $01FF Stack
* $0200 - $03FF Mostly Free, Input Buffer, Interrupt Vectors
* $0400 - $07FF Lo-res/Text Page1
* $0800 - $0BFF Lo-res/Text Page2 (BASIC programs load here)
* $0C00 - $1FFF Free
* $2000 - $3FFF Hi-res Page1
* $4000 - $5FFF Hi-res Page2
* $6000 - $95FF Free
* $9600 - $BFFF DOS3.3 and Buffers
* $C000 - $CFFF Soft Switches, Expansion Card I/O and ROM
* $D000 - $F7FF BASIC ROM (can be bankswitched later models)
* $F800 - $FFFF Machine Language Monitor ROM (also can be bankswitched)
DSK MORE ;WRITE ASSEMBLED FILE TO DISK
TYP $06 ;$FF=SYSTEM, $06=BINARY
ORG $2000 ;ASSEMBLE START ADDRESS
* SYSTEM VARIABLES
*
IN .EQ $200 ;256-CHAR INPUT BUF
*
* SUBROUTINES IN MONITOR ROM: $F800 - $FFFF
*
RDKEY .EQ $FD0C ;READS A CHARACTER
GETLN .EQ $FD6A ;READS A LINE, WITH PROMPT($33)
GETLN1 .EQ $FD6F ;READS A LINE, NO PROMPT
CROUT .EQ $FD8E
COUT .EQ $FDED
PRBYTE .EQ $FDDA
*
* SUBROUTINES IN BASIC.SYSTEM ROM:
GETBUFR EQU $BEF5 ;BCC=OKAY & A=HIBYTE OF BUF
;BCS=FAIL & A=ERRCODE
;X & Y ARE DESTROYED
FREEBUFR EQU $BEF8 ;FREE BUFFER
* PRODOS ENTRY POINT
PRODOS_MLI EQU $BF00 ;MACHINE LANG IFACE (MLI)
*
* MEMORY MAPPED I/O: $C000 - $CFFF
*
RD80VID EQU $C01F ;<=128->40COL, >128->80COL
*
* SLOT 3 SCRATCHPAD RAM - TEXT PAGE 0 SCREEN HOLE
* http://yesterbits.com/media/books/apple/heiserman-1983-intermediate-level-apple-ii-handbook.pdf
*
OURCH EQU $057B ;80-COL HORIZ CURSOR POSITION
OURCV EQU $05FB ;VERTICAL CURSOR POSITION
* ZERO-PAGE ADDRESSES
*
ZP.A1L .EQ $3C ;MONITOR GENERAL PURPOSE
ZP.A1H .EQ $3D ;MONITOR GENERAL PURPOSE
*
* PRODOS COMMAND CODES
*
OPENCMD .EQ $C8
READCMD .EQ $CA
CLOSCMD .EQ $CC
*
* CONSTANTS
*
EOFERR .EQ $4C ;ERROR CODE FOR END-OF-FILE
PTR .EQ $06 ;ONLY FREE 0-PAGE LOCATION
MAXERCDE .EQ $5A ;LARGEST ERROR CODE
CR .EQ $0D ;ASCII CARRIAGE RETURN
CR.HIBIT .EQ $8D ;CARRIAGE RET WITH HIGH BIT SET
BUFSIZE .EQ $00FF
SCR.HGHT .EQ 24 ;SCREEN HEIGHT
*
* DEBUGGING
TRACE EQU 0
********************************
* *
* PUSH Y ONTO THE STACK *
* DESTROYS A *
* *
********************************
PUSHY .MA
TYA
PHA
.EM
********************************
* *
* POP Y FROM THE STACK *
* DESTROYS A *
* *
********************************
POPY .MA
PLA
TAY
.EM
********************************
* *
* COPY IN BUF TO STRING *
* *
* X CONTAINS LENGTH OF "IN" *
* ]1 IS DEST STRING (LEN BYT) *
* A IS DESTROYED *
* *
********************************
CPIN .MA
PUSHY ;SAVE Y
STX ]1 ;COPY LENGTH TO FIRST BYTE OF ]1
LDY #0 ;INIT Y TO ZERO
:1 CPY ]1 ;COMPARE Y WITH LENGTH BYTE
BEQ :2 ;DONE IF LENGTH IS REACHED
LDA IN,Y ;LOAD IN[Y] INTO ACCUMULATOR
CMP #CR ;COMPARE WITH CARRIAGE RETURN
BEQ :2 ;STOP AT CARRIAGE RETURN
INY ;DEST STR IS 1 AHEAD OF IN BUF
STA ]1,Y ;COPY CHAR TO DEST STR ]1
JMP :1 ;LOOP TO NEXT CHAR
:2 POPY ;RESTORE Y
.EM
********************************
* *
* WRITES A LENGTH PREFIXED *
* STRING TO THE SCREEN *
* A IS DESTROYED *
* *
********************************
PUTS .MA
PUSHY
LDY #0 ;INIT LOOP INDEX
:1 CPY ]1 ;HAS STR LENGTH BEEN REACHED
BEQ :2 ;IF SO THEN FINISH
INY ;MOVE TO INDEX OF NEXT CHAR
LDA ]1,Y ;GET THE CHAR TO BE WRITTEN
JSR COUT ;WRITE THE CHARACTER
JMP :1 ;LOOP
:2 POPY
.EM
********************************
* *
* SET TO #1 (IMMEDIATE 1) *
* ]1 DESTINATION *
* A IS DESTROYED *
* *
********************************
SET1 .MA
LDA #1
STA ]1
.EM
SET0 .MA
LDA #0
STA ]1
.EM
SET23 .MA
LDA #23
STA ]1
.EM
********************************
* *
* MAIN PROGRAM *
* *
********************************
MAIN CLD ;CLEAR DECIMAL FLG, AVOID CRASH
>SET0 USRQUIT ;INITIALIZE TO "NO"
*
* GET FILE NAME
*
PUTS INFOLINE
JSR CROUT
:ASKFILE PUTS PROMPT
JSR GETLN1 ;LENGTH IN X, CR AT END
CPX #0 ;IS THE LENGTH ZERO?
BNE :CONT0 ;USER JUST PRESSED RETURN
JMP :END
:CONT0 CPX #1
BNE :CONT1
LDA #"?"
CMP IN
BNE :CONT1
JSR HELPINFO
JMP :ASKFILE
:CONT1 CPIN FILENAME ;COPY "IN" BUF TO FILENAME
DO TRACE
JSR PRSTRBYTES
JSR GETLN
FIN
*
* GET FILE I/O BUFFER FOR OPEN CALL
*
LDA #4 ;FOUR 256 BYTE PAGES = 1KB
JSR GETBUFR ;GET BUF FROM BASIC.SYSTEM
BCC :CONT2 ;CARRY CLEAR MEANS NO ERROR
JSR OBUFERR
JMP :END
:CONT2 STA OBUFADDR+1 ;GETBUFR RETURNS HIBYTE IN A
LDA #0 ;PREPARE
STA OBUFADDR ;LOBYTE IS 0 B/C ADDR OF PAGE
*
* OPEN FILE
*
JSR PRODOS_MLI
DB OPENCMD
DA OPENPRMS
BEQ :CONT3
JSR OPENERR
JSR FREEBUFR ;CLEAN UP BEFORE TRY AGAIN
JMP :ASKFILE
*
* COPY FILE NUMBER FROM OPEN PARAMETERS TO READ AND CLOSE
*
:CONT3 LDA OPENFNUM
STA READFNUM
STA CLOSFNUM
*
* GET BUFFER FOR READ OPERATION FROM BASIC.SYSTEM
*
LDA #1 ;ONE 256 BYTE BUFFER
JSR GETBUFR ;CALL BASIC.SYSTEM SUB
BCC :CONT4
JSR RBUFERR ;CARRY SET MEANS ERROR
JMP :CLOSFILE
:CONT4 STA RBADDR+1 ;STORE HI-BYTE
STA ZP_A1H ;FOR 0-PAGE INDIRECTION
LDA #0 ;0 FOR LO-BYTE
STA RBADDR ;STORE IT
STA ZP.A1L ;AGAIN, FOR 0-PAGE INDIRECTION
*
* PRINT THE FILE
*
JSR VIEWFILE
*
* CLEANUP
*
JSR FREEBUFR ;FREE READ BUFFER
*
* Close file
*
:CLOSFILE JSR PRODOS_MLI ;CLOSE THE FILE
DB CLOSCMD
DA CLOSPRMS
BEQ :FREEOBUF
JSR CLOSERR
:FREEOBUF JSR FREEBUFR ;FREE OPEN I/O BUFFER
:END NOP
RTS
********************************
* *
* END OF MAIN - PROGRAM EXIT *
* *
********************************
********************************
* *
* PROGRAM INFO AND HELP *
* *
********************************
HELPINFO JSR CROUT
PUTS INFO0
JSR CROUT
PUTS INFO1
JSR CROUT
PUTS INFO2
JSR CROUT
PUTS INFO3
JSR CROUT
PUTS INFO4
JSR CROUT
JSR CROUT
RTS
********************************
* *
* HANDLE ERROR WHEN OPENING *
* FILE *
* *
********************************
OPENERR STA ERRCODE
PUTS OERRMSG
PUTS FILENAME
LDA #":"
JSR COUT
LDA ERRCODE
JSR ERRPROC
RTS
********************************
* *
* HANDLE ERROR WHEN CLOSING *
* FILE *
* *
********************************
CLOSERR STA ERRCODE
PUTS CERRMSG
PUTS FILENAME
LDA #"'"
JSR COUT
LDA #":"
JSR COUT
LDA ERRCODE
JSR ERRPROC
RTS
********************************
* *
* HANDLE ERROR WHEN REQUESTING *
* READ BUFFER *
* *
********************************
RBUFERR STA ERRCODE
PUTS RBERRMSG
LDA #":"
JSR COUT
LDA ERRCODE
JSR ERRPROC
RTS
********************************
* *
* HANDLE ERROR WHEN REQUESTING *
* READ BUFFER *
* *
********************************
OBUFERR STA ERRCODE
PUTS OBERRMSG
LDA #":"
JSR COUT
LDA ERRCODE
JSR ERRPROC
RTS
********************************
* *
* PRINT "IN" BUFFER *
* *
********************************
PRINT_IN
PUSHY
LDA #"X"
JSR COUT
LDA #"="
JSR COUT
TXA
JSR PRBYTE
JSR CROUT
LDY #0
:LOOP CPY #255
BEQ :ENDLOOP
LDA IN,Y
JSR PRBYTE
LDA #" "
JSR COUT
INY
JMP :LOOP
:ENDLOOP JSR CROUT
POPY
RTS
********************************
* *
* PRINT STRING BYTES *
* *
********************************
PRSTRBYTES
PUSHY
LDY #0
:LOOP CPY #255
BEQ :ENDLOOP
LDA FILENAME,Y
JSR PRBYTE
LDA #" "
JSR COUT
INY
JMP :LOOP
:ENDLOOP JSR CROUT
POPY
RTS
********************************
* *
* VIEW FILE SUB *
* *
********************************
VIEWFILE
DO TRACE
>PUTS ENVIEW
FIN
SET1 LINENUM ;INIT LINE NUMBER
:LOOP JSR PRODOS_MLI ;CALL PRODOS TO READ FILE
DB READCMD ;SPECIFY PRODOS READ COMMAND
DA READPRMS ;READ PARAMETERS
BNE :READERR
JSR WRITEBUF ;WRITE TO SCREEN WHAT WAS READ
LDA #1 ;PREPARE FOR NEXT OP
CMP USRQUIT ;IF USER WANTS TO QUIT, THEN
BEQ :ENDLOOP ;EXIT THE LOOP
JMP :LOOP ;ELSE, GET THE NEXT BUFFER
:READERR JSR ERRPROC
:ENDLOOP NOP
RTS
********************************
* *
* WRITE BUFFER TO SCREEN *
* *
********************************
WRITEBUF
>PUSHY
LDY #0 ;INIT CHAR COUNTER VARIABLE
.1 CPY READCNT ;COMPARE TO MAX CHARS
BEQ .3
LDA (ZP.A1L),Y ;GET CHAR FROM BUFFER
ORA #%10000000 ;TURN ON HIGH BIT FOR PRINTING
JSR COUT ;COUT PRESERVES ACCUM
*
* CHECK END OF LINE
*
CMP #CR.HIBIT ;COMPARE TO CARRIAGE RETURN
BNE .2 ;IF NOT END OF LINE, NEXT CHAR
INC LINENUM ;NEXT LINE HAS BEEN REACHED
*
* CHECK AT END OF PAGE
*
LDA LINENUM
CMP #SCR.HGHT ;AT BOTTOM OF SCREEN?
BNE .2 ;NO? THEN NEXT CHAR
JSR STATBAR ;YES? THEN SHOW THE STATUS BAR
LDA #1 ;SETUP FOR NEXT LINE
CMP USRQUIT ;DID USER ASK TO QUIT
BEQ .3 ;YES? THEN END SUB
.2 INY ;STATBAR HAS ADJUSTED LINENUM
JMP .1
.3 >POPY
DO TRACE
PUTS EXWRITEBUF
FIN
RTS
********************************
* *
* PRINT ASCII IN HEX *
* *
********************************
PRASCII PHA
LDA #"["
JSR COUT
PLA
JSR PRBYTE
LDA #"]"
JSR COUT
LDA #" "
JSR COUT
RTS
********************************
* *
* DO THE STATUS BAR *
* *
********************************
STATBAR
DO TRACE
>PUTS ENSTATB
FIN
>PUSHY
>PUTS BAR
.1 JSR RDKEY ;GET A KEY FROM THE USER
CMP #" " ;CHECK IF SPACE ENTERED
BNE .2 ;IF NOT FORWARD TO NEXT CHECK
>SET1 LINENUM ;ADVANCE ONE PAGE, STORE 1
JMP .4 ;PROCESSED SPACE SO DONE
.2 CMP #CR.HIBIT ;CHECK FOR CARRIAGE RETURN
BNE .3
>SET23 LINENUM
JMP .4
.3 CMP #"Q" ;USER WANTS TO QUIT
BNE .1 ;NO RECOGNIZED INPUT
>SET1 USRQUIT
.4 JSR ERASEBAR
>POPY
DO TRACE
>PUTS EXSTATB
FIN
RTS
********************************
* *
* ERASE STATUS BAR *
* *
********************************
ERASEBAR
DO TRACE
>PUTS ENERASEB
FIN
>PUSHY
>SET0 OURCH ;RESET CURSOR TO BEG OF LINE
LDY #0 ;INIT COUNTER FOR SPACES
.1 CPY BAR ;FIRST BYTE IS LENGTH
BEQ .2 ;IF Y=LEN THEN DONE
LDA #" " ;LOAD SPACE
JSR COUT ;WRITE TO SCREEN
INY ;MAKE PROGRESS
JMP .1 ;LOOP TO NEXT CHAR
.2 >SET0 OURCH ;RESET CURSON TO BEG OF LINE
POPY
DO TRACE
>PUTS EXERASEB
FIN
RTS
********************************
* *
* ERROR HANDLER *
* INPUT PARAM: A HOLDS ERRCODE *
* *
********************************
ERRPROC
STA ERRCODE
CMP #0
BNE :EEOF
JMP :END
:EEOF CMP #EOFERR
BNE :E01
JMP :END
:E01 CMP #1
BNE :E04
PUTS E01MSG
JMP :END
:E04 CMP #4
BNE :E25
PUTS E04MSG
JMP :END
:E25 CMP #$25
BNE :E27
PUTS E25MSG
JMP :END
:E27 CMP #$27
BNE :E28
PUTS E27MSG
JMP :END
:E28 CMP #$28
BNE :E2B
PUTS E28MSG
JMP :END
:E2B CMP #$2B
BNE :E2E
PUTS E2BMSG
JMP :END
:E2E CMP #$2E
BNE :E40
PUTS E2EMSG
JMP :END
:E40 CMP #$40
BNE :E42
PUTS E40MSG
JMP :END
:E42 CMP #$42
BNE :E43
PUTS E42MSG
JMP :END
:E43 CMP #$43
BNE :E44
PUTS E43MSG
JMP :END
:E44 CMP #$44
BNE :E45
PUTS E44MSG
JMP :END
:E45 CMP #$45
BNE :E46
PUTS E45MSG
JMP :END
:E46 CMP #$46
BNE :E47
PUTS E46MSG
JMP :END
:E47 CMP #$47
BNE :E48
PUTS E47MSG
JMP :END
:E48 CMP #$48
BNE :E49
PUTS E48MSG
JMP :END
:E49 CMP #$49
BNE :E4A
PUTS E49MSG
JMP :END
:E4A CMP #$4A
BNE :E4B
PUTS E4AMSG
JMP :END
:E4B CMP #$4B
BNE :E4C
PUTS E4BMSG
JMP :END
:E4C CMP #$4C
BNE :E4D
PUTS E4CMSG
JMP :END
:E4D CMP #$4D
BNE :E4E
PUTS E4DMSG
JMP :END
:E4E CMP #$4E
BNE :E50
PUTS E4EMSG
JMP :END
:E50 CMP #$50
BNE :E51
PUTS E50MSG
JMP :END
:E51 CMP #$51
BNE :E52
PUTS E51MSG
JMP :END
:E52 CMP #$52
BNE :E53
PUTS E52MSG
JMP :END
:E53 CMP #$53
BNE :E55
PUTS E53MSG
JMP :END
:E55 CMP #$55
BNE :E56
PUTS E55MSG
JMP :END
:E56 CMP #$56
BNE :E57
PUTS E56MSG
JMP :END
:E57 CMP #$57
BNE :E5A
PUTS E57MSG
JMP :END
:E5A CMP #$5A
BNE :E_UNK
PUTS E5AMSG
JMP :END
:E_UNK PUTS E_UNK_MSG
LDA #":"
JSR COUT
LDA ERRCODE
JSR PRBYTE
:END JSR CROUT
RTS
********************************
* *
* DATA DIVISION HAHA *
* *
********************************
INFOLINE STR "ENTER [?] FOR PROGRAM INFO AND HELP"
INFO0 STR "MORE - PAGES THROUGH TEXT FILE"
INFO1 STR "COPYRIGHT (C) 2024 BILL CHATFIELD"
INFO2 STR "DISTRIBUTED UNDER THE GPL VERSION 3"
INFO3 STR "https://github.com/gungwald/prodos-more"
INFO4 STR "PRESS RETURN TO QUIT"
PROMPT STR "FILE:"
ERRTXT STR "ERROR:"
FILENAME DS $FF
ERRCODE DS 1
LINENUM DS 1
BAR STR '[RET] LINE [SPC] PAGE [Q]UIT'
USRQUIT DS 1
BUFCHAR DS 1
USRCHAR DS 1
OERRMSG STR "CANNOT OPEN "
CERRMSG STR "CANNOT CLOSE "
RBERRMSG STR "CANNOT CREATE READ BUFFER"
OBERRMSG STR "CANNOT CREATE FILE BUFFER"
E00MSG STR "NO ERROR"
E01MSG STR "BAD SYSTEM CALL NUMBER"
E04MSG STR "BAD SYSTEM CALL PARAMETER COUNT"
E25MSG STR "INTERRUPT TABLE FULL"
E27MSG STR "I/O ERROR"
E28MSG STR "NO DEVICE CONNECTED"
E2BMSG STR "DISK WRITE PROTECTED"
E2EMSG STR "DISK SWITCHED"
E40MSG STR "INVALID PATHNAME"
E42MSG STR "MAXIMUM NUMBER OF FILES OPEN"
E43MSG STR "INVALID REFERENCE NUMBER"
E44MSG STR "DIRECTORY NOT FOUND"
E45MSG STR "VOLUME NOT FOUND"
E46MSG STR "FILE NOT FOUND"
E47MSG STR "DUPLICATE FILENAME"
E48MSG STR "VOLUME FULL"
E49MSG STR "VOLUME DIRECTORY FULL"
E4AMSG STR "INCOMPATIBLE FILE FORMAT OR PRODOS DIRECTORY"
E4BMSG STR "UNSUPPORTED STORAGE TYPE"
E4CMSG STR "END OF FILE ENCOUNTERED"
E4DMSG STR "POSITION OUT OF RANGE"
E4EMSG STR "FILE ACCESS ERROR OR FILE LOCKED"
E50MSG STR "FILE IS OPEN"
E51MSG STR "DIRECTORY STRUCTURE DAMAGED"
E52MSG STR "NOT A PRODOS VOLUME"
E53MSG STR "INVALID SYSTEM CALL PARAMETER"
E55MSG STR "VOLUME CONTROL BLOCK TABLE FULL"
E56MSG STR "BAD BUFFER ADDRESS"
E57MSG STR "DUPLICATE VOLUME"
E5AMSG STR "FILE STRUCTURE DAMAGED"
E_UNK_MSG STR "UNKNOWN ERROR CODE"
ENVIEW STR 'ENTERING VIEWFILE'
EXVIEW STR 'EXITING VIEWFILE'
EXWRITEBUF STR 'EXITING WRITEBUF'
ENSTATB STR 'ENTERING STATUSBAR'
EXSTATB STR 'EXITING STATUSBAR'
ENERASEB STR 'ENTERING ERASEBAR'
EXERASEB STR 'EXITING ERASEBAR'
*
* OPEN PARAMETERS
*
OPENPRMS .DA #3
.DA FILENAME
OBUFADDR .BS 2
OPENFNUM .BS 1
*
* READ PARAMETERS
*
READPRMS .DA #4
READFNUM .BS 1
RBADDR .BS 2
REQCNT .DA BUFSIZE
READCNT .BS 2
*
* CLOSE PARAMETERS
*
CLOSPRMS .DA #1
CLOSFNUM .BS 1
*
* BUFFERS
*
* CONSUME ALL BYTES UP TO THE NEXT PAGE BOUNDRY
*FILLER DS \,$00
* MUST START ON PAGE BOUNDRY
*OPENBUF DS 1024
*READBUF DS BUFSIZE