*
********************************
*                              *
*      -< COMMON DEMO )-       *
*                              *
*        VERSION 0.3.0         *
*                              *
*         10-JAN-2019          *
*                              *
********************************
*                              *
*       NATHAN D. RIGGS        *
*   NATHAN.RIGGS@OUTLOOK.COM   *
*                              *
********************************
*
** ASSEMBLER DIRECTIVES
*
         CYC   AVE
         EXP   ONLY
         TR    ON
         DSK   COMMON.DEMO
         OBJ   $BFE0
         ORG   $6000
*
*``````````````````````````````*
*  TOP INCLUDES (HOOKS,MACROS) *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
         PUT   REQUIRED.VARS
         USE   REQUIRED.MAC.MIN
         PUT   REQUIRED.HOOKS.MIN
         USE   COMMON.MAC.MIN
         PUT   COMMON.HOOKS.MIN
*
*``````````````````````````````*
*      PROGRAM MAIN BODY       *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
** MFILL DOES ABOUT WHAT ITS NAME
** IMPLIES: IT FILLS A BLOCK OF MEMORY
** WITH A PARTICULAR CHARACTER.
*
         _PRNT " ",8D8D
         MFILL #$300;#10;#0
         _PRNT "MFILL FILLS A PORTION OF MEMORY WITH",8D
         _PRNT "A SPECIFIED VALUE. ",8D8D
         _DUMP $300;#10
         _WAIT
*
** MMOVE ALSO DOES WHAT IT SAYS: IT MOVES
** A BLOCK OF MEMORY FROM A SOURCE LOCATION
** TO A DESTINATION LOCATION. WE'LL NOW MOVE
** THOSE ZEROES PLACED BY MEMFILL TO ANOTHER
** LOCATION.
*
         _PRNT " ",8D8D
         _PRNT "MMOVE COPIES A SPAN OF MEMORY",8D
         _PRNT "FROM A SOURCE TO A DESTINATION ADDRESS.",8D8D
         _PRNT "SO MOVING $300 TO $320 RESULTS IN:",8D8D
         MMOVE $300;$320;#10
         _DUMP $320;#10
         _WAIT
*
** DELAY RUNS THROUGH CYCLES OF THE
** 6502 UNTIL A CERTAIN AMOUNT OF TIME
** HAS PASSED.
*
         _PRNT " ",8D8D
         _PRNT "DELAY DELAYS A SPECIFIED NUMBER OF",8D
         _PRNT "MILLISECONDS. 250 MILLISECONDS = 1/4 SECOND.",8D8D
*
         DELAY #250       ;  TIME IN MILLISECONDS
                          ; IS PASSED VIA Y
                          ; 250 = 1/4 SECOND
         BEEP  1
         _PRNT "1/4 SECOND",8D
         DELAY #250
         BEEP  2
         _PRNT "1/4 SECOND",8D
         DELAY #250
         BEEP  3
         _PRNT "1/4 SECOND",8D
         DELAY #250
         BEEP  4
         _PRNT "1/4 SECOND",8D
*
         _PRNT " ",8D8D
         _WAIT
*
** ZSAVE BACKS UP THE "FREE" AREAS OF
** THE ZERO PAGE TO AN ALTERNATE MEMORY
** LOCATION. THIS IS MOSTLY USEFUL WHEN
** YOU KNOW A ROUTINE USES THE ZERO PAGE,
** BUT YOU WANT TO KEEP THE VALUES CURRENTLY
** STORED THERE AFTER CALLING THE ROUTINE.
*
** NOTE THAT SINCE THE LIBRARY MAKES HEAVY USE
** OF THESE MEMORY ADDRESSES, ANY TIME YOUR CODE
** MAKES USE OF THE ZERO PAGE, IT IS ADVISED TO
** SAVE THE STATE BEFORE CALLING ANY OTHER ROUTINES.
*
         LDA   #01
         STA   $06
         LDA   #02
         STA   $07
         LDA   #03
         STA   $08
         LDA   #04
         STA   $09
         ZSAVE $300
*
         _PRNT " ",8D8D
         _PRNT "ZSAVE SAVES THE STATE OF THE ZERO PAGE ",8D
         _PRNT "ADDRESSES THAT ARE NOT USED BY DOS,",8D
         _PRNT "APPLESOFT,PRODOS OR INTEGER BASIC.",8D8D
         _PRNT "SO THE BACKED UP ZERO PAGE AT $300 IS:",8D8D
         _DUMP $300;#18
         _PRNT " ",8D8D
         _PRNT "18 BYTES ARE USED.",8D8D
         _WAIT
*
** YOU CAN RESTORE THE ZERO PAGE TO ITS
** PRIOR STATE BY THEN CALLING ZLOAD.
*
         ZLOAD $300
*
         _PRNT " ",8D8D
         _PRNT "YOU CAN THEN RESTORE THE FREE ZERO PAGE",8D
         _PRNT "LOCATIONS WITH ZLOAD. THERE ISN'T ANY",8D
         _PRNT "MEANINGFUL OUTPUT TO PUT HERE TO ",8D
         _PRNT "ILLUSTRATE THAT, SO USE YOUR IMAGINATION!",8D8D
         _WAIT
*
** THE MSWAP MACRO SWAPS THE MEMORY BLOCK AT ONE
** ADDRESS WITH THE SAME LENGTH AT ANOTHER.
*
         _PRNT "THE MSWAP MACRO SWAPS A LENGTH",8D
         _PRNT "OF MEMORY FROM ONE LOCATION",8D
         _PRNT "TO ANOTHER. SO, BEFORE SWAP:",8D8D
         _DUMP $300;#10
         _DUMP $320;#10
         MSWAP $300;$320;#10
         _PRNT " ",8D
         _PRNT "AND AFTER SWAP: ",8D8D
         _DUMP $300;#10
         _DUMP $320;#10
         _WAIT
*
         JMP   REENTRY
*
*``````````````````````````````*
*        BOTTOM INCLUDES       *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
** BOTTOM INCLUDES
*
         PUT   REQUIRED.LIB.MIN
*
** INDIVIDUAL SUBROUTINE INCLUDES
*
*  COMMON LIBRARY SUBROUTINES
*
         PUT   MEMFILL.SUB.MIN
         PUT   MEMMOVE.SUB.MIN
         PUT   DELAYMS.SUB.MIN
         PUT   ZMSAVE.SUB.MIN
         PUT   ZMLOAD.SUB.MIN
         PUT   MEMSWAP.SUB.MIN