*
********************************
*                              *
*      -< STRINGS DEMO >-      *
*                              *
*       VERSION 00.00.01       *
*                              *
*         03/04/1980           *
*                              *
********************************
*                              *
*       NATHAN D. RIGGS        *
*   NATHAN.RIGGS@OUTLOOK.COM   *
*                              *
********************************
*
** ASSEMBLER DIRECTIVES
*
         CYC   AVE
         EXP   ONLY
         DSK   STRINGS.DEMO
*
*``````````````````````````````*
*  TOP INCLUDES (PUTS, MACROS) *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
         PUT   DECS
         USE STRINGS.MAC
*
         PUT   STRINGS.HOOKS
*
         OBJ   $BFE0
         ORG $6000
*
*``````````````````````````````*
*      PROGRAM MAIN BODY       *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
*
*
** BIG LUMPS -- HIGH LEVEL CODE
*
*
** STRCMP COMPARES TWO STRINGS, THEN
** SETS THE STATUS REGISTER AS FOLLOWS:
*
** Z=1 IF STRINGS ARE IDENTICAL
** Z=0 IF STRINGS NOT IDENTICAL
** C=1 IF STRING2 LENGTH IS >
** C=0 IF STRING1 LENGTH IS >
*
** MACRO:
*
         JMP   CONT
STR1     STR   "THIZ IS STRING1"
STR2     STR   "THIS IS STRING 2"
CONT
         LDA   #>STR1
         PHA
         LDA   #<STR1
         PHA
         LDA   #>STR2
         PHA
         LDA   #<STR2
         PHA
         JSR   STRCMP
* BRK ; P = 31 = 00110001; Z=0,C=1
*
*
** STRCAT CONCATENATES TWO STRINGS AND RETURNS
** THE CONCATENATED STRING WHERE THE FIRST
** STRING WAS STORED.
*
** MACRO:
*
         JMP   CATCON
CATSTR   STR   "ABC"
BLANK    STR   "   "
CATSTR2  STR   "DEF"
*
CATCON
         LDA   #>CATSTR
         PHA
         LDA   #<CATSTR
         PHA
         LDA   #>CATSTR2
         PHA
         LDA   #<CATSTR2
         PHA
         LDA   #7         ; MAX SIZE OF CAT
         PHA
         JSR   STRCAT
         LDX   #>CATSTR
         LDY   #<CATSTR
* BRK ; X,Y HOLDS LOW AND HIGH BYTES OF
* THE ADDRESS TO THE CONCATENATED STRING.
* IF YOU LIST THAT ADDRESS, YOU SHOULD SEE
* THAT THE FIRST LOCATION HOLDS THE LENGTH
* OF THE NEW STRING (06), FOLLOWED BY THE
* HEXADECIMAL CODES FOR THE CHARACTERS
* ABCDEF: C1 C2 C3 C4 C5 C6
*
*
*
** PRNSTR PRINTS THE STRING AT THE SPECIFIED
** MEMORY ADDRESS TO COUT1.
*
** MACRO:
*
         LDA   #>CATSTR   ; FROM PREVIOUS EXAMPLE
         PHA
         LDA   #<CATSTR
         PHA
         JSR   PRNSTR
* BRK ; YOU SHOULD SEE
* "ABCDEF" APPENDED TO THE LINE WHERE YOU
* TYPED "BRUN STRINGS.DEMO." USE ROUTINES FROM
* STDIO FOR PLACEMENT OF THE TEXT.
*
*
*
*
         JMP   NUMSTRX
NUMSTR   HEX   2B67       ;11111
NUMSTRX
*
         LDA   #>$300     ; DESTINATION
         PHA
         LDA   #<$300
         PHA
         LDA   #>11111    ; VALUE TO CONVERT
         PHA
         LDA   #<11111
         PHA
         JSR   NUM2STR
*BRK
*
* $300 SHOULD NOW HOLD 05,B1,B1,B1,B1,B1
*
*
*
** STR2NUM DOES THE OPPOSITE OF NUM2STR: IT
** RETURNS THE NUMBER EQUIVALENT OF A STRING
** AND HOLDS THEM IN X (HIGH) AND Y (LOW)
*
         LDA   #>$300     ; STRING FROM PREVIOUS
         PHA
         LDA   #<$300
         PHA
         JSR   STR2NUM
*BRK ; X,Y HOLDS 2B67, #11111
*
*
** SUBPOS RETURNS THE POSITION OF A SUBSTRING
** WITHIN A PARENT STRING.
*
         LDA   #>STR      ; STRING ADDRESS
         PHA
         LDA   #<STR
         PHA
         LDA   #>SUB      ; SUBSTRING ADDRESS
         PHA
         LDA   #<SUB
         PHA
         JSR   SUBPOS
         JMP   SUBPOSX
STR      STR   "THIS IS A TEST"
SUB      STR   "IS A TEST"
SUBPOSX
*BRK ; A = 06
*
*
** SUBCOPY COPIES A SUBSTRING AT THE SPECIFIED
** POSITION TO A PARTICULAR MEMORY ADDRESS
*
         LDA   #>STR11    ; SOURCE STRING
         PHA
         LDA   #<STR11
         PHA
         LDA   #5         ; INDEX TO START COPY
         PHA
         LDA   #5         ; LENGTH TO COPY
         PHA
         LDA   #>STR21
         PHA
         LDA   #<STR21
         PHA
         LDA   #15        ; MAX LENGTH OF STRING 2
         PHA
         JSR   SUBCOPY
         JMP   STRCOPYX
STR11    STR   "0123456789012345"
STR21    STR   "000000000000000000"
STRCOPYX
         LDX   #>STR21
         LDY   #<STR21    ; ADDRESS OF STR2
*BRK ; LOCATION FOR STR21 SHOULD NOW START WITH
* 4,5,6,7,8
*
*
** SUBDEL DELETES A SUBSTRING FROM A GIVEN STRING
** AND CHANGES THE STRING SIZE ACCORDINGLY.
** MIN POSITION IS 1, NOT 0
*
         LDA   #>STR11    ; STRING LOCATION
         PHA
         LDA   #<STR11
         PHA
         LDA   #1         ; STARTING INDEX FOR DELETE
         PHA
         LDA   #5         ; LENGTH TO DELETE
         PHA
         JSR   SUBDEL
         LDX   #>STR11
         LDY   #<STR11
*BRK ; FIRST 5 DIGITS ARE DELETED, REMAINING STRING
* STORED ANEW
*
*
** SUBINS INSERTS A SOURCE STRING
** INTO ANOTHER DESTINATION STRING, MOVING THE
** CONTENTS AND ADJUSTING LENGTH AS NECESSARY.
*
         LDA   #>INS1     ; DESTINATION
         PHA
         LDA   #<INS1
         PHA
         LDA   #3         ; INDEX
         PHA
         LDA   #200       ; MAXLEN OF NEW STRING
         PHA
         LDA   #>INS2     ; SOURCE SUBSTRING
         PHA
         LDA   #<INS2
         PHA
         JSR   SUBINS
         LDY   #<INS1
         LDX   #>INS1
*BRK ; MEMLOC IN XY NOW HAS INS2 INSERTED INTO INS1
* AT LOCATION 3
*
** DATA
*
INS1     STR   "XXXXXXXXX"
ZZZ      STR   "999999999"
INS2     STR   "111111111"
*
*
*
*
** LITTLE LUMPS -- MID/LOW LEVEL
*
*
         JMP   REENTRY
*
*``````````````````````````````*
*        BOTTOM INCLUDES       *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
*
** BOTTOM INCLUDES
*
         PUT   STRINGS.LIB
         PUT   SUBSTRINGS.LIB
*