Screen clipping works when 80-col card is active

Separated code into files for S-C and Merlin

.gitignore

@@ -0,0 +1,4 @@
+MORE
+MORE.dsk
+_FileInformation.txt
+*.swp

Makefile

@@ -24,9 +24,9 @@ endif
 # It is necessary to use this older version of AppleCommander to support
 # the PowerBook G4 and iBook G3. This version only requires Java 1.3.
 AC=java -jar AppleCommander-1.3.5-ac.jar
-SRC=more.s
-PGM=more
-BASE_DSK=prodos-2.0.3-boot.dsk
+SRC=more.merlin.s
+PGM=MORE
+BASE_DSK=prodos-2.0.3.dsk
 VOL=$(PGM)
 DSK=$(PGM).dsk
 
@@ -35,12 +35,13 @@ DSK=$(PGM).dsk
 # disk instead.
 #$(AC) -pro140 $(DSK) $(VOL)
 
-$(DSK): $(PGM)
+$(DSK): $(PGM) test.txt
 	$(COPY) $(BASE_DSK) $(DSK)
-	$(AC) -p $(DSK) $(PGM) BIN 0x8000 < $(PGM)
+	$(AC) -p $(DSK) $(PGM) BIN 0x2000 < $(PGM)
+	cat test.txt | tr '\n' '\r' | $(AC) -p $(DSK) TEST TXT
 
 $(PGM): $(SRC) Makefile
-	merlin32 --verbose $(SRC)
+	merlin32 $(SRC)
 
 clean:
 	$(RM) $(DSK) $(PGM) *.zip _FileInformation.txt $(PGM)_Output.txt

more.bas

@@ -0,0 +1,89 @@
+ 10  REM  *****************************
+ 15  REM  *                           *
+ 20  REM  * MORE   - TEXT FILE VIEWER *
+ 30  REM  * AUTHOR - BILL CHATFIELD   *
+ 35  REM  *                           *
+ 40  REM  *****************************
+ 44 :
+ 45  REM  TODO:
+ 46  REM  CD,PREFIX,PWD,CWD,CHDIR,FASTER OUTPUT
+ 47  REM  PREFIX IN PROMPT
+ 48  REM  DETAILED HELP FROM "?" COMMAND, FIX FIRST LINE
+ 49 :
+ 50  LET D$ =  CHR$ (4)
+ 55  LET BS$ =  CHR$ (7)
+ 56  LET CR$ =  CHR$ (13)
+ 57  LET PROMPT$ = "[RETURN] NEXT LINE   [SPACE] NEXT PAGE   [Q] QUIT"
+ 58  LET LINE = 1
+ 59  PRINT "ENTER A FILE NAME, * FOR CATALOG, OR JUST HIT RETURN TO ABORT
+     ."
+ 60  INPUT "FILE:";F$
+ 70  IF  RIGHT$ (F$,1) = "*" THEN  PRINT D$;"CATALOG "; LEFT$ (F$, LEN (F
+     $) - 1): GOTO 60
+ 80  IF F$ = "" THEN  END 
+ 85  IF F$ = "?" THEN 59
+ 110  ONERR  GOTO 5050: REM  SETUP ERROR HANDLER
+ 125  PRINT D$;"VERIFY ";F$: REM  CHECK IF FILE EXISTS, ERROR CODE 6
+ 130  PRINT D$;"OPEN ";F$: REM  WILL CREATE FILE IF IT DOES NOT EXIST.
+ 140  PRINT D$;"READ ";F$
+ 150  GET C$
+ 160  PRINT C$;
+ 165  IF C$ = CR$ THEN LINE = LINE + 1
+ 167  IF LINE = 24 THEN  INVERSE : PRINT PROMPT$;: NORMAL : PRINT D$: GOSUB 
+     4000: GOSUB 3000: GOTO 140
+ 170  GOTO 150: REM  NEXT CHARACTER IN FILE
+ 180  REM  END OF MAIN, BUT UNREACHABLE BECAUSE OF CHARACTER LOOP
+ 3000  REM  ****************
+ 3005  REM  *              *
+ 3010  REM  * ERASE PROMPT *
+ 3015  REM  *              *
+ 3020  REM  ****************
+ 3025  LET PL =  LEN (PROMPT$)
+ 3030  POKE 1403,0: REM  BACKUP TO BEGINNING OF LINE
+ 3060  PRINT  SPC( PL): REM  ERASE PROMPT
+ 3070  POKE 1403,0: REM  BACKUP AGAIN
+ 3080  RETURN 
+ 4000  REM  ***************
+ 4005  REM  *             *
+ 4010  REM  * GET COMMAND *
+ 4015  REM  *             *
+ 4020  REM  ***************
+ 4030  GET CMD$
+ 4040  IF CMD$ = CR$ THEN LINE = 23: GOTO 4060
+ 4050  IF CMD$ = " " THEN LINE = 1: GOTO 4060
+ 4055  IF CMD$ = "Q" OR CMD$ = "q" THEN  PRINT D$;"CLOSE": PRINT D$: PRINT 
+     : END 
+ 4060  RETURN 
+ 5000  REM  *****************
+ 5010  REM  *               *
+ 5020  REM  * ERROR HANDLER *
+ 5030  REM  *               *
+ 5040  REM  *****************
+ 5050  POKE 216,0: REM  TURNS OFF 'ONERR GOTO' ERROR HANDLING
+ 5060  LET ERRCODE =  PEEK (222): REM  GETS THE CODE FOR THIS ERROR
+ 5070  PRINT D$;"CLOSE": REM  CLOSES ANY OPEN FILES
+ 5080  PRINT D$: REM  TURNS OFF FILE I/O SO PRINTS GO TO SCREEN
+ 5090  IF ERRCODE = 5 THEN 5290: REM  END-OF-FILE IS NOT AN ERROR
+ 5100  PRINT : PRINT : REM  SEPARATES ERR MSG FROM ANY PREVIOUS OUTPUT
+ 5120  REM  CHECK FOR DOS/PRODOS ERRORS NOT IN APPLESOFT TABLE
+ 5130  IF ERRCODE = 6 THEN  PRINT "ERROR:FILE NOT FOUND:";F$
+ 5140  IF ERRCODE = 11 THEN  PRINT "ERROR:INVALID OPTION"
+ 5150  IF ERRCODE = 255 THEN  PRINT : PRINT : PRINT "INTERRUPTED BY CTRL-C"
+ 5155  GOTO 5290: REM  SKIP TO THE END
+ 5160  REM  COPY ERROR MESSAGE FROM APPLESOFT ERROR TABLE
+ 5170  LET BASE = 53856: REM  $D260, START OF APPLESOFT ERR TABLE
+ 5180  LET PTR = BASE + ERRCODE: REM  POINT TO 1ST BYTE OF ERR MSG
+ 5185  PRINT "ERROR:";: REM  PREFIX ALL PRINTED MESSAGES WITH THIS
+ 5190 :
+ 5195  REM  LOOP TO PRINT CHARS OF ERR MSG FROM APPLESOFT ERROR TABLE
+ 5200  REM  WHILE (THERE ARE MORE CHARS IN MESSAGE) DO
+ 5210  LET BYTE =  PEEK (PTR): REM  GETS BYTE POINTED TO BY PTR
+ 5220  IF BYTE >  = 128 THEN 5280: REM  DETECTS LAST BYTE
+ 5230  PRINT  CHR$ (BYTE);: REM  CNVTS ASCII BYTE TO CHAR, PRINT
+ 5240  LET PTR = PTR + 1: REM  ADVANCES POINTER TO NEXT BYTE
+ 5250  GOTO 5210: REM  LOOPS BACK TO NEXT BYTE
+ 5260  REM  END WHILE
+ 5270 :
+ 5280  PRINT  CHR$ (BYTE - 128);: REM  SETS HIGH BIT TO 0, PRINT
+ 5290  END : REM  THIS IS THE END - JIM MORRISON
+

more.c

@@ -1,20 +0,0 @@
-/*
- * more.c
- *
- *  Created on: Jan 4, 2020
- *      Author: bill
- */
-
-int main(int argumentCount, char *arguments)
-{
-	int i;
-	int exitCode;
-
-	if (argumentCount == 0)
-		exitCode = more(askUserForFile());
-	else
-		for (i = 1; i < argumentCount; ++i)
-			exitCode = more(arguments[i]);
-
-	return exitCode;
-}

more.merlin.s

@@ -0,0 +1,971 @@
+********************************
+*                              *
+* MORE - UN*X MORE COMMAND     *
+* ASSEMBLES WITH MERLIN        *
+*                              *
+********************************
+
+* 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)
+*
+* Branching
+*
+* CMP,CPX,CPY ->
+* Condition 	        N 	Z 	C
+* Register < Memory 	1 	0 	0
+* Register = Memory 	0 	1 	1
+* Register > Memory 	0 	0 	1 
+*
+* BPL - BRANCH PLUS (N=0) NOT NEGATIVE
+* BMI - BRANCH MINUS (N=1) NEGATIVE
+* BEQ - BRANCH EQUAL (Z=1) ZERO FLAG SET
+* BNE - BRANCH NOT EQUAL (Z=0) ZERO FLAG NOT SET
+* BCC - BRANCH CARRY CLEAR (C=0)
+* BCS - BRANCH CARRY SET (C=1)
+* BVC - BRANCH OVERVLOW CLEAR (V=0)
+* BVS - BRANCH OVERFLOW SET (V=1)
+
+                DSK     MORE        ;WRITE ASSEMBLED FILE TO DISK
+                TYP     $06         ;$FF=SYSTEM, $06=BINARY
+                ORG     $2000       ;ASSEMBLE START ADDRESS
+*
+* SYSTEM VARIABLES
+*
+PTR             EQU     06          ;ONLY FREE 0-PAGE LOCATION
+CH              EQU     $24         ;40-COL HORZ CURS POSITION
+CV              EQU     $25         ;40-COL VERT CURS POSITION
+PROMPT          EQU     $33         ;PROMPT CHARACTER
+ZP_A1L          EQU     $3C         ;MONITOR GENERAL PURPOSE
+ZP_A1H          EQU     $3D         ;MONITOR GENERAL PURPOSE
+IN              EQU     $200        ;256-CHAR INPUT BUF
+*
+* 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
+*
+* SUBROUTINES IN MONITOR ROM: $F800 - $FFFF
+*
+CR              EQU     $FC62       ;CURSOR TO BEG OF NEXT LINE
+RDKEY           EQU     $FD0C       ;READS A CHARACTER
+GETLN           EQU     $FD6A       ;READS A LINE, WITH PROMPT($33)
+GETLN1          EQU     $FD6F       ;READS A LINE, NO PROMPT
+CROUT           EQU     $FD8E
+COUT            EQU     $FDED
+PRBYTE          EQU     $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
+*
+KBD             EQU     $C000       ;KEYBOARD DATA AND STROBE
+CXROMOFF        EQU     $C006       ;SELECT SLOT ROMS
+CXROMON         EQU     $C007       ;SELECT INTERNAL ROM
+KBDSTRB         EQU     $C010       ;CLEAR KEYBOARD STROBE
+ALTCHAR         EQU     $C01E       ;CHARACTER SET STATUS
+RD80VID         EQU     $C01F       ;<=128->40COL, >128->80COL
+INVERT          EQU     $CEDD       ;INVERT CHARACTER ON SCREEN
+PICK            EQU     $CF01       ;PICK CHARACTER OFF SCREEN
+*
+* PRODOS COMMAND CODES
+*
+GET_PREFIX      EQU     $C7
+OPEN            EQU     $C8
+READ            EQU     $CA
+CLOSE           EQU     $CC
+*
+* PRODOS MLI PARAMETER COUNTS
+*
+GETPRFXPARMCNT  EQU     1
+OPENPARMCNT     EQU     3
+READPARMCNT     EQU     4
+CLOSEPARMCNT    EQU     1
+*
+* ASCII
+*
+CR_CHAR         EQU     $0D         ;ASCII CARRIAGE RETURN
+CR_HIBIT        EQU     $8D         ;CARRIAGE RET WITH HIGH BIT SET
+*
+* CONSTANTS
+*
+EOFERR          EQU     $4C         ;ERROR CODE FOR END-OF-FILE
+MAXERCDE        EQU     $5A         ;LARGEST ERROR CODE
+BUFSIZE         EQU     $00FF
+SCR_HGHT        EQU     24          ;SCREEN HEIGHT
+*
+* DEBUGGING
+*
+TRACE           EQU     0
+
+********************************
+*                              *
+* PUSH Y ONTO THE STACK        *
+* DESTROYS A                   *
+*                              *
+********************************
+
+PUSHY          MAC
+               TYA
+               PHA
+               <<<
+
+********************************
+*                              *
+* POP Y FROM THE STACK         *
+* DESTROYS A                   *
+*                              *
+********************************
+
+POPY           MAC
+               PLA
+               TAY
+               <<<
+
+********************************
+*                              *
+* COPY IN BUF TO STRING        *
+*                              *
+* X CONTAINS LENGTH OF "IN"    *
+* ]1 IS DEST STRING (LEN BYT)  *
+* A IS DESTROYED               *
+*                              *
+********************************
+
+CPIN           MAC
+               PUSHY            ;SAVE Y
+               STX   ]1         ;COPY LENGTH TO FIRST BYTE OF ]1
+               LDY   #0         ;INIT Y TO ZERO
+LOOP           CPY   ]1         ;COMPARE Y WITH LENGTH BYTE
+               BEQ   ENDLOOP    ;DONE IF LENGTH IS REACHED
+               LDA   IN,Y       ;LOAD IN[Y] INTO ACCUMULATOR
+               CMP   #CR_CHAR   ;COMPARE WITH CARRIAGE RETURN
+               BEQ   ENDLOOP    ;STOP AT CARRIAGE RETURN
+               INY              ;DEST STR IS 1 AHEAD OF IN BUF
+               STA   ]1,Y       ;COPY CHAR TO DEST STR ]1
+               JMP   LOOP       ;LOOP TO NEXT CHAR
+ENDLOOP        POPY             ;RESTORE Y
+               <<<
+
+********************************
+*                              *
+* WRITES A LENGTH PREFIXED     *
+* STRING TO THE SCREEN         *
+* A IS DESTROYED               *
+*                              *
+********************************
+
+PUTS           MAC
+               PUSHY
+               LDY   #0         ;INIT LOOP INDEX
+LOOP           CPY   ]1         ;HAS STR LENGTH BEEN REACHED
+               BEQ   ENDLOOP    ;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   LOOP       ;LOOP
+ENDLOOP        POPY
+               <<<
+
+********************************
+*                              *
+* SET TO #1 (IMMEDIATE 1)      *
+* ]1 DESTINATION               *
+* A IS DESTROYED               *
+*                              *
+********************************
+
+SET1           MAC
+               LDA   #1
+               STA   ]1
+               <<<
+
+SET0           MAC
+               LDA   #0
+               STA   ]1
+               <<<
+
+SET23          MAC
+               LDA   #23
+               STA   ]1
+               <<<
+
+********************************
+*                              *
+* STANDARD ASSEM LANG          *
+* BACKWARDS COPY OF 1 BYTE     *
+* A IS DESTROYED               *
+* ]1 DESTINATION               *
+* ]2 SOURCE                    *
+*                              *
+********************************
+
+COPY_B      MAC
+            LDA     ]2
+            STA     ]1
+            <<<
+
+********************************
+*                              *
+* MAIN PROGRAM                 *
+*                              *
+********************************
+
+MAIN           CLD                  ;CLEAR DECIMAL FLG, AVOID CRASH
+               SET0  USRQUIT        ;INITIALIZE TO "NO"
+               JSR   GET_SCRN_WDTH
+*
+* GET PREFIX TO SEE IF IT IS SET
+*
+               JSR   PRODOS_MLI
+               DB    GET_PREFIX
+               DA    GETPRFXPARMS
+               BEQ   :CHKPREFIX
+               JSR   GETPRFXERR
+               JMP   :END
+:CHKPREFIX     LDA   PREFIX
+               CMP   #0
+               BNE   :GETFILE
+               JSR   CROUT
+               PUTS  WARNING
+               PUTS  NOPREFIXMSG
+               JSR   CROUT
+               JSR   CROUT
+*
+* GET FILE NAME
+*
+:GETFILE       PUTS  INFOLINE
+               JSR   CROUT
+:ASKFILE       PUTS  FILEPROMPT
+               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    OPEN
+               DA    OPENPARMS
+               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    CLOSE  
+               DA    CLOSEPARMS
+               BEQ   :FREEOBUF
+               JSR   CLOSERR
+               
+:FREEOBUF      JSR   FREEBUFR   ;FREE OPEN I/O BUFFER
+:END           NOP
+               RTS
+
+********************************
+*                              *
+* END OF MAIN - PROGRAM EXIT   *
+*                              *
+********************************
+
+********************************
+*                              *
+* DETERMINE IF SCREEN IS IN    *
+* 40 COL OR 80 COL MODE        *
+*                              *
+********************************
+GET_SCRN_WDTH   LDA     #%10000000      ;USE ALTCHARSET STATUS TO
+                BIT     ALTCHAR         ;SEE IF 80-COL CARD TURNED ON
+                BMI     :CARD_ACTIVE    ;BIT 7 ON = NEG & CARD ACTIVE
+                JMP     :FORTY_COLUMNS  ;INACTIVE CARD IS 40-COL
+:CARD_ACTIVE    LDA     #%10000000      ;SEE IF CARD IS IN 40/80 MODE
+                BIT     RD80VID         ;BIT 7 OFF = 0 OR >0 & 40-COL
+                BMI     :EIGHTY_COLUMNS ;BIT 7 ON = NEG & 80-COL MODE
+:FORTY_COLUMNS  LDA     #40
+                STA     SCR_WDTH
+                JMP     :END
+:EIGHTY_COLUMNS LDA     #80
+                STA     SCR_WDTH
+:END            
+                DO      TRACE
+                LDA     ALTCHAR
+                JSR     PRBYTE
+                JSR     CROUT
+                LDA     RD80VID
+                JSR     PRBYTE
+                JSR     CROUT
+                PUTS    SCR_WDTH_TXT
+                LDA     SCR_WDTH
+                JSR     PRBYTE
+                JSR     CROUT
+                FIN
+
+                RTS
+
+********************************
+*                              *
+* 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 GETTING    *
+* PREFIX                       *
+*                              *
+********************************
+GETPRFXERR     STA   ERRCODE
+               PUTS  GETPRFXERRMSG
+               LDA   #":"
+               JSR   COUT
+               LDA   ERRCODE
+               JSR   ERRPROC
+               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
+            
+            COPY_B  SCRNLINE;#1 ;INIT SCREEN LINE NUMBER
+            COPY_B  LINEIDX;#1  ;POSITION IN LINE
+:LOOP       JSR     PRODOS_MLI  ;CALL PRODOS TO READ FILE
+            DB      READ        ;SPECIFY PRODOS READ COMMAND
+            DA      READPARMS   ;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
+:LOOP       CPY     READCNT     ;COMPARE TO MAX CHARS
+            BEQ     :ENDLOOP
+            LDA     (ZP_A1L),Y  ;GET CHAR FROM BUFFER
+            ORA     #%10000000  ;TURN ON HIGH BIT FOR PRINTING
+            JSR     WRITECHAR   ;COUT PRESERVES ACCUM
+*
+* CHECK AT END OF PAGE
+*
+            LDA     SCRNLINE    ;CURSOR VERTICAL SCREEN LINE
+            CMP     #SCR_HGHT   ;AT BOTTOM OF SCREEN?
+            BNE     :CONT       ;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     :ENDLOOP    ;YES? THEN END SUB
+:CONT       INY                 ;STATBAR HAS ADJUSTED LINENUM
+            JMP     :LOOP
+:ENDLOOP    NOP
+            POPY
+
+            DO      TRACE
+            PUTS    EXWRITEBUF
+            FIN
+
+            RTS
+
+********************************
+*                              *
+* WRITE CHAR TO SCREEN         *
+* CLIPS TO SCREEN WIDTH        *
+*                              *
+********************************
+WRITECHAR   STA     CHAR        ;DON'T LOOSE THE CHARACTER
+            CMP     #CR_HIBIT   ;COMPARE TO CARRIAGE RETURN
+            BNE     :NOT_EOL    ;IF NOT END OF LINE, PRINT
+            JSR     DOWN1LINE
+            JMP     :ENDSUB     ;NOTHING MORE TO DO FOR EOL
+:NOT_EOL    LDA     LINEIDX     ;GET CURSOR HORIZ COL
+            CMP     SCR_WDTH    ;COMPARE WITH SCREEN WIDTH
+            BPL     :FORWARD    ;DON'T PRINT IF OFF SCREEN
+            LDA     CHAR        ;ON SCREEN, SO PRINT IT
+            JSR     COUT
+:FORWARD    INC     LINEIDX
+:ENDSUB     RTS
+
+********************************
+*                              *
+* GO TO BEGINNING OF NEXT LINE *
+*                              *
+********************************
+DOWN1LINE   INC     SCRNLINE    ;KEEP TRACK OF LINE NUMBER
+            COPY_B  LINEIDX;#1  ;RESET TO BEGINNING OF LINE
+            ;COPY_B  OURCH;#0
+            JSR     CROUT       ;LINE DOWN & SCROLL IF NEEDED
+            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
+:LOOP          JSR   RDKEY      ;GET A KEY FROM THE USER
+               CMP   #" "       ;CHECK IF SPACE ENTERED
+               BNE   :CHKCR     ;IF NOT FORWARD TO NEXT CHECK
+               SET1  SCRNLINE   ;ADVANCE ONE PAGE, STORE 1
+               JMP   :ENDLOOP   ;PROCESSED SPACE SO DONE
+:CHKCR         CMP   #CR_HIBIT  ;CHECK FOR CARRIAGE RETURN
+               BNE   :CHKQUIT
+               SET23 SCRNLINE
+               JMP   :ENDLOOP
+:CHKQUIT       CMP   #"Q"       ;USER WANTS TO QUIT
+               BEQ   :QUITTING  ;NO RECOGNIZED INPUT
+               CMP   #"q"
+               BEQ   :QUITTING
+               JMP   :LOOP
+:QUITTING      SET1  USRQUIT
+:ENDLOOP       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
+:LOOP          CPY   BAR        ;FIRST BYTE IS LENGTH
+               BEQ   :ENDLOOP   ;IF Y=LEN THEN DONE
+               LDA   #" "       ;LOAD SPACE
+               JSR   COUT       ;WRITE TO SCREEN
+               INY              ;MAKE PROGRESS
+               JMP   :LOOP      ;LOOP TO NEXT CHAR
+:ENDLOOP       SET0  OURCH      ;RESET CURSOR 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"
+FILEPROMPT     STR   "FILE:"
+ERRTXT         STR   "ERROR:"
+FILENAME       DS    $FF
+PREFIX         DS    64
+ERRCODE        DS    1
+SCRNLINE       DS    1
+LINEIDX        DS    1
+CHAR           DS    1
+BAR            STR   '[RET] LINE  [SPC] PAGE  [Q]UIT'
+USRQUIT        DS    1
+BUFCHAR        DS    1
+USRCHAR        DS    1
+SCR_WDTH       DS    1
+SCR_WDTH_TXT   STR  "SCREEN WIDTH="
+
+PREFIXMSG   STR     "THE PREFIX IS "
+WARNING     STR     'WARNING'
+NOPREFIXMSG STR     ": NO PREFIX IS SET. YOU MUST ENTER THE FULL PATH TO THE FILE."
+GETPRFXERRMSG STR   "CANNOT GET PREFIX"
+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'
+*
+* GET_PREFIX PARAMETERS
+*
+GETPRFXPARMS   DB    #GETPRFXPARMCNT
+PREFIXADDR     DA    PREFIX
+*
+* OPEN PARAMETERS
+*
+OPENPARMS      DB    #OPENPARMCNT
+               DA    FILENAME
+OBUFADDR       DS    2
+OPENFNUM       DS    1
+*
+* READ PARAMETERS
+*
+READPARMS      DB    #READPARMCNT
+READFNUM       DS    1
+RBADDR         DS    2
+REQCNT         DW    BUFSIZE
+READCNT        DS    2
+*
+* CLOSE PARAMETERS
+*
+CLOSEPARMS     DB    #CLOSEPARMCNT
+CLOSFNUM       DS    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

more.s

@@ -1,402 +0,0 @@
-*
-* more - Text viewer
-*
-
-* BEQ - Branch if Equal
-*   Branches if the zero flag (Z) is set to 1. This happens if:
-*       - A 0 value is loaded into the accumulator via LDA
-*       - A CMP is done on two equal values
-*       - A SBC is done on two equal values?
-* BCC - Branch if Carry Flag is Clear
-*   Equivalent to Branch if Less Than (BLT), meaning that the
-*   accumulator (A) is less than the parameter: A < Param
-* BGE - Branch if Accum >= Param is BCS
-
-PROMPT  equ $33
-BUFF    equ $200
-
-* System subroutines stored in Monitor ROM
-GETLN   equ $fd6a   ; Reads a line of input, with prompt from $33
-GETLNZ  equ $fd67   ; Reads a line of input, CR first
-GETLN1  equ $fd6f   ; Reads a line of input, no prompt
-CROUT   equ $fd8e   ; Outputs a carriage return
-PRBYTE  equ $fdda   ; Outputs a byte
-COUT    equ $fded   ; Outputs a character
-
-* MLI stands for Machine Language Interface
-* It is the ProDOS system call entry point
-MLI     equ $bf00
-
-* ProDOS system call command codes
-OPEN    equ $c8
-READ    equ $ca
-CLOSE   equ $cc
-
-* Constants
-EOF     equ $4c     ; End of file
-PTR     equ $06
-MAX_EC  equ $5a     ; The largest error code
-CR      equ $0d     ; Carriage return
-BUF_SIZ equ $00ff
-
-
-WRITE_CHAR  mac
-            if  #=]1
-                lda ]1
-            else
-                lda #]1
-            fin
-            jsr COUT
-            eom
-
-
-WRITE_BYTE  mac
-            lda ]1
-            jsr PRBYTE
-            eom
-
-
-WRITE_ASC   mac
-            tya         ; Preserve Y by transferring it to A
-            pha         ;  and pushing it onto the stack
-            ldy #0      ; Prepare loop index
-nextch      lda ]1,Y    ; Load a character into A
-            beq finish  ; Branch if lda loaded a zero value
-            jsr COUT    ; Write the character in A
-            iny         ; Increment Y
-            jmp nextch  ; Go back and load the next character
-finish      pla         ; Restore Y by pulling stack into A
-            tay         ;  and transferring it to Y
-            eom
-
-
-WRITE_STR   mac
-            tya             ; Preserve Y
-            pha
-            lda ]1          ; Length byte
-            sta len
-            ldy #1          ; Prepare loop index
-nextChar    tya
-            cmp len         ; Check if beyond end of string
-            bcc writeChar   ; Y is Less than
-            beq writeChar   ; or equal to len
-            jmp finish
-writeChar   lda ]1,y        ; Load a character
-            jsr COUT
-            iny
-            jmp nextChar
-len         db  0
-finish      pla             ; Restore Y
-            tay
-            eom
-
-
-COPY_BYTE   mac
-            lda ]1
-            sta ]2
-            eom
-
-* Copies a line out of BUFF into ]1.
-* Length is in X as is done by GETLN.
-COPY_BUFF   mac
-            tya             ; Preserve Y register
-            pha             ;  by pushing it on the stack
-            txa             ; Transfer X to A for compare
-            cmp #$ff        ; Check if string is too long
-            bne startCopy   ; If not, get started
-            dex             ; If so, shrink to fit with length byte
-startCopy   stx ]1          ; Store length to target string
-            ldy #0          ; Initialize loop index
-nextChar    tya             ; Move current position to A
-            cmp ]1          ; Compare current position with length
-            beq endCopyLine ; Quit if we've reached the end
-            lda BUFF,y      ; Load current character
-            iny             ; BUFF and ]1 are off by 1 because of len byte
-            sta ]1,y        ; Store character into target string
-            jmp nextChar    ; Continue with next character
-endCopyLine pla             ; Restore Y by pulling value from stack
-            tay             ;  and transferring to Y
-            eom
-
-WRITE_BUFF  mac
-            tya
-            pha
-            stx len
-            ldy #0
-nextByte    tya
-            cmp len
-            beq done
-            lda BUFF,y
-            jsr COUT
-            iny
-            jmp nextByte
-done        pla
-            tay
-            eom
-
-* Starting at $9000 because:
-* $800 overwrites Applesoft
-* $803 is where Applesoft programs start
-* $2000 is where the current .SYSTEM program is loaded
-
-mainProgram
-            org $8000
-
-getFileNam
-            WRITE_ASC prompt
-            COPY_BYTE #"?";PROMPT
-            jsr GETLN1
-            WRITE_ASC buffText
-            WRITE_BUFF
-            jsr CROUT
-            COPY_BUFF fileName
-
-openFile    jsr MLI
-            db  OPEN
-            da  openParams
-            bne openErrorHandler
-
-readFile    COPY_BYTE fileNum;readNum
-readNext    jsr MLI
-            db  READ
-            da  readParams
-            cmp #EOF
-            beq closeFile
-            cmp #0
-            bne readErrorHandler
-
-writeScreen 
-            ldy #0
-            sty lineCount
-            sty charCount
-nextChar    lda readIoBuf,y
-            inc charCount
-            ora #$80
-            jsr COUT
-            cmp $0d
-            bne continue
-            inc lineCount
-continue    cpy #<BUF_SIZ
-            beq readNext
-            iny
-            jmp nextChar
-
-closeFile   COPY_BYTE fileNum;closeNum
-            jsr MLI
-            db  CLOSE
-            dw  closeParams
-            bne closeErrorHandler
-            jmp endMain
-openErrorHandler
-            sta errorCode
-            WRITE_ASC openFailureText
-            jmp errorHandler
-readErrorHandler
-            sta errorCode
-            WRITE_ASC readFailureText
-            jmp errorHandler
-closeErrorHandler
-            sta errorCode
-            WRITE_ASC closeFailureText
-errorHandler
-            WRITE_STR fileName
-            WRITE_CHAR ":"
-            WRITE_CHAR " "
-            lda errorCode
-            cmp #MAX_EC         ; Compare by A - MAX_EC
-            bcs unknownError    ; Branch if A >= MAX_EC
-            lda errorCode       ; Necessary?
-            clc                 ; Prepare for addition
-            adc errorCode       ; Double for indexing addresses
-            tax
-            lda errorMessages,x
-            sta PTR
-            inx
-            lda errorMessages,x
-            sta PTR+1
-            bne writeError
-            lda PTR
-            bne writeError
-unknownError
-            WRITE_ASC unknownErrorCodeText
-            WRITE_CHAR "$"
-            WRITE_BYTE errorCode
-            jsr CROUT
-            jmp endMain 
-writeError
-            WRITE_ASC (PTR)
-            WRITE_CHAR " "
-            WRITE_ASC errorCodeText
-            WRITE_CHAR "$"
-            WRITE_BYTE errorCode
-            WRITE_CHAR ")"
-            jsr CROUT
-endMain
-            COPY_BYTE #"]";PROMPT   ; Restore normal prompt
-            rts
-
-* DAT-uh
-
-openParams  db  3           ; Parameter count
-oPathPtr    da  fileName    ; Input param - file to open
-oBufPtr     da  openIoBuf   ; Input param - I/O buffer
-fileNum     ds  1           ; Output param - file ref num
-
-readParams  db  4
-readNum     ds  1
-            da  readIoBuf
-reqCount    dw  BUF_SIZ
-transCount  ds  2
-
-closeParams db  1           ; Parameter count
-closeNum    db  0           ; Input param - ref num to close
-
-fileName    ds  $ff         ; String starting with length byte
-
-charCount   ds  2
-lineCount   ds  1
-len         ds  1
-
-buffText         asc "BUFF=",00
-prompt           asc "ENTER FILE NAME: ",00
-errorCode        db  0
-openFailureText  asc "FAILED TO OPEN FILE ",00
-readFailureText  asc "FAILED TO READ FILE ",00
-closeFailureText asc "FAILED TO CLOSE FILE ",00
-errorCodeText    asc "(ERROR CODE ",00
-
-unknownErrorCodeText asc "UNKNOWN ERROR CODE: ",00
-em00    asc "NO ERROR",00
-em01    asc "BAD SYSTEM CALL NUMBER",00
-em03    asc "NO DEVICE CONNECTED",00    ; Bug in AppleWin < 1.26.3.0
-em04    asc "BAD SYSTEM CALL PARAMETER COUNT",00
-em25    asc "INTERRUPT VECTOR TABLE FULL",00
-em27    asc "I/O ERROR",00
-em28    asc "DEVICE NOT CONNECTED",00
-em2b    asc "DISK WRITE PROTECTED",00
-em2e    asc "DISK SWITCHED WHILE FILE STILL OPEN",00
-em40    asc "PATH CONTAINS ILLEGAL CHARACTERS",00
-em42    asc "CANNOT EXCEED 8 OPEN FILES",00
-em44    asc "PATH NOT FOUND",00
-em45    asc "VOLUME DIRECTORY NOT FOUND",00
-em46    asc "FILE NOT FOUND",00
-em47    asc "DUPLICATE FILENAME",00
-em48    asc "DISK IS FULL",00
-em49    asc "CANNOT EXCEED 51 DIRECTORY ENTRIES",00
-em4a    asc "INCOMPATIBLE FILE FORMAT",00
-em4b    asc "UNSUPPORTED STORAGE TYPE",00
-em4c    asc "END OF FILE",00
-em4d    asc "FILE POSITION OUT OF RANGE",00
-em4e    asc "FILE ATTRIBUTE FORBIDS OPERATION",00
-em50    asc "FILE IS OPEN",00
-em51    asc "DIRECTORY COUNT ERROR",00
-em52    asc "NOT A PRODOS DISK",00
-em55    asc "VOLUME CONTROL BLOCK FULL",00
-em56    asc "BAD BUFFER ADDRESS",00
-em57    asc "DUPLICATE VOLUME",00
-em5a    asc "BIT MAP DISK ADDRESS IS IMPOSSIBLE",00
-*
-* ERROR CODE TO MESSAGE TRANSLATION TABLE
-*
-errorMessages
-ec00    da  em00
-ec01    da  em01
-ec02    da  $0000
-ec03    da  em03    ; Bug in AppleWin < 1.26.3.0
-ec04    da  em04
-ec05    da  $0000
-ec06    da  $0000
-ec07    da  $0000
-ec08    da  $0000
-ec09    da  $0000
-ec0a    da  $0000
-ec0b    da  $0000
-ec0c    da  $0000
-ec0d    da  $0000
-ec0e    da  $0000
-ec0f    da  $0000
-ec10    da  $0000
-ec11    da  $0000
-ec12    da  $0000
-ec13    da  $0000
-ec14    da  $0000
-ec15    da  $0000
-ec16    da  $0000
-ec17    da  $0000
-ec18    da  $0000
-ec19    da  $0000
-ec1a    da  $0000
-ec1b    da  $0000
-ec1c    da  $0000
-ec1d    da  $0000
-ec1e    da  $0000
-ec1f    da  $0000
-ec20    da  $0000
-ec21    da  $0000
-ec22    da  $0000
-ec23    da  $0000
-ec24    da  $0000
-ec25    da  $0000
-ec26    da  $0000
-ec27    DA  em27
-ec28    DA  em28
-ec29    da  $0000
-ec2a    da  $0000
-ec2b    da  $0000
-ec2c    da  $0000
-ec2d    da  $0000
-ec2e    DA  em2e
-ec2f    da  $0000
-ec30    da  $0000
-ec31    da  $0000
-ec32    da  $0000
-ec33    da  $0000
-ec34    da  $0000
-ec35    da  $0000
-ec36    da  $0000
-ec37    da  $0000
-ec38    da  $0000
-ec39    da  $0000
-ec3a    da  $0000
-ec3b    da  $0000
-ec3c    da  $0000
-ec3d    da  $0000
-ec3e    da  $0000
-ec3f    da  $0000
-ec40    da  em40
-ec41    da  $0000
-ec42    da  em42
-ec43    da  $0000
-ec44    da  em44
-ec45    da  em45
-ec46    da  em46
-ec47    da  em47
-ec48    da  em48
-ec49    da  em49
-ec4a    da  em4a
-ec4b    da  em4b
-ec4c    da  em4c
-ec4d    da  em4d
-ec4e    da  em4e
-ec4f    da  $0000
-ec50    da  em50
-ec51    da  em51
-ec52    da  em52
-ec53    da  $0000
-ec54    da  $0000
-ec55    da  em55
-ec56    da  em56
-ec57    da  em57
-ec58    da  $0000
-ec59    da  $0000
-ec5a    da  em5a
-*
-* Consume all bytes up to next page boundary
-*
-filler  ds  \,$00
-*
-* Must start on page boundary
-*
-openIoBuf   ds  1024
-readIoBuf   ds  BUF_SIZ
-

more.sc.s

@@ -0,0 +1,813 @@
+********************************
+*                              *
+* 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

test.txt

@@ -0,0 +1,195 @@
+MORE(1)                          User Commands                         MORE(1)
+
+NAME
+       more - display the contents of a file in a terminal
+
+SYNOPSIS
+       more [options] file ...
+
+DESCRIPTION
+       more is a filter for paging through text one screenful at a time. This
+       version is especially primitive. Users should realize that less(1)
+       provides more(1) emulation plus extensive enhancements.
+
+OPTIONS
+       Options are also taken from the environment variable MORE (make sure to
+       precede them with a dash (-)) but command-line options will override
+       those.
+
+       -d, --silent
+           Prompt with "[Press space to continue, 'q' to quit.]", and display
+           "[Press 'h' for instructions.]" instead of ringing the bell when an
+           illegal key is pressed.
+
+       -l, --logical
+           Do not pause after any line containing a ^L (form feed).
+
+       -e, --exit-on-eof
+           Exit on End-Of-File, enabled by default if POSIXLY_CORRECT
+           environment variable is not set or if not executed on terminal.
+
+       -f, --no-pause
+           Count logical lines, rather than screen lines (i.e., long lines are
+           not folded).
+
+       -p, --print-over
+           Do not scroll. Instead, clear the whole screen and then display the
+           text. Notice that this option is switched on automatically if the
+           executable is named page.
+
+       -c, --clean-print
+           Do not scroll. Instead, paint each screen from the top, clearing
+           the remainder of each line as it is displayed.
+
+       -s, --squeeze
+           Squeeze multiple blank lines into one.
+
+       -u, --plain
+           Suppress underlining. This option is silently ignored as backwards
+           compatibility.
+
+       -n, --lines number
+           Specify the number of lines per screenful. The number argument is a
+           positive decimal integer. The --lines option shall override any
+           values obtained from any other source, such as number of lines
+           reported by terminal.
+
+       -number
+           A numeric option means the same as --lines option argument.
+
+       +number
+           Start displaying each file at line number.
+
+       +/string
+           The string to be searched in each file before starting to display
+           it.
+
+       -h, --help
+           Display help text and exit.
+
+       -V, --version
+           Print version and exit.
+
+COMMANDS
+       Interactive commands for more are based on vi(1). Some commands may be
+       preceded by a decimal number, called k in the descriptions below. In
+       the following descriptions, ^X means control-X.
+
+       h or ?
+           Help; display a summary of these commands. If you forget all other
+           commands, remember this one.
+
+       SPACE
+           Display next k lines of text. Defaults to current screen size.
+
+       z
+           Display next k lines of text. Defaults to current screen size.
+           Argument becomes new default.
+
+       RETURN
+           Display next k lines of text. Defaults to 1. Argument becomes new
+           default.
+
+       d or ^D
+           Scroll k lines. Default is current scroll size, initially 11.
+           Argument becomes new default.
+
+       q or Q or INTERRUPT
+           Exit.
+
+       s
+           Skip forward k lines of text. Defaults to 1.
+
+       f
+           Skip forward k screenfuls of text. Defaults to 1.
+
+       b or ^B
+           Skip backwards k screenfuls of text. Defaults to 1. Only works with
+           files, not pipes.
+
+       '
+           Go to the place where the last search started.
+
+       =
+           Display current line number.
+
+       /pattern
+           Search for kth occurrence of regular expression. Defaults to 1.
+
+       n
+           Search for kth occurrence of last regular expression. Defaults to
+           1.
+
+       !command or :!command
+           Execute command in a subshell.
+
+       v
+           Start up an editor at current line. The editor is taken from the
+           environment variable VISUAL if defined, or EDITOR if VISUAL is not
+           defined, or defaults to vi(1) if neither VISUAL nor EDITOR is
+           defined.
+
+       ^L
+           Redraw screen.
+
+       :n
+           Go to kth next file. Defaults to 1.
+
+       :p
+           Go to kth previous file. Defaults to 1.
+
+       :f
+           Display current file name and line number.
+
+       .
+           Repeat previous command.
+
+ENVIRONMENT
+       The more command respects the following environment variables, if they
+       exist:
+
+       MORE
+           This variable may be set with favored options to more.
+
+       SHELL
+           Current shell in use (normally set by the shell at login time).
+
+       TERM
+           The terminal type used by more to get the terminal characteristics
+           necessary to manipulate the screen.
+
+       VISUAL
+           The editor the user prefers. Invoked when command key v is pressed.
+
+       EDITOR
+           The editor of choice when VISUAL is not specified.
+
+       POSIXLY_CORRECT
+           Disable exit-on-eof (see option -e for more details).
+
+HISTORY
+       The more command appeared in 3.0BSD. This man page documents more
+       version 5.19 (Berkeley 6/29/88), which is currently in use in the Linux
+       community. Documentation was produced using several other versions of
+       the man page, and extensive inspection of the source code.
+
+AUTHORS
+       Eric Shienbrood, UC Berkeley.
+
+       Modified by Geoff Peck, UCB to add underlining, single spacing.
+
+       Modified by John Foderaro, UCB to add -c and MORE environment variable.
+
+SEE ALSO
+       less(1), vi(1)
+
+REPORTING BUGS
+       For bug reports, use the issue tracker at
+       https://github.com/util-linux/util-linux/issues.
+
+AVAILABILITY
+       The more command is part of the util-linux package which can be
+       downloaded from Linux Kernel Archive
+       <https://www.kernel.org/pub/linux/utils/util-linux/>.
+
+util-linux 2.39.3                 2023-11-21                           MORE(1)