*-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=*
*                              *
* MATH.MAC                     *
*                              *
* AUTHOR:  NATHAN RIGGS        *
* CONTACT: NATHAN.RIGGS@       *
*          OUTLOOK.COM         *
*                              *
* VERSION: 0.1.2               *
* DATE:    30-OCT-2018         *
* ASSEMBLER: MERLIN 8 PRO      *
*                              *
* LICENSE: APACHE 2.0 LICENSE, *
*  WHERE APPLICABLE. CODE      *
*  INSPIRED BY OR COPIED FROM  *
*  OTHERS MAY FALL UNDER A     *
*  DIFFERENT LICENSE. I WILL   *
*  DO MY BEST TO NOTIFY SUCH   *
*  CASES.                      *
*                              *
*------------------------------*
*                              *
* THIS IS A MACRO LIBRARY FOR  *
* MATH.LIB, AND CAN BE USED    *
* REGARDLESS OF WHETHER A      *
* SPECIFIC FUNCTION IS         *
* INCLUDED AS A PUT IN THE     *
* MAIN SOURCE.                 *
*                              *
*------------------------------*
*                              *
* LIST OF MACROS               *
*                              *
* _ADD16 : 16BIT ADD           *
* _SUB16 : 16BIT SUBTRACT      *
* _MUL16 : 16BIT MULTIPLY      *
* _DIV16 : 16BIT DIVIDE        *
* _REM16 : 16BIT REMAINDER     *
* _RND8 : RANDOM # 0..255      *
* _RNDB : RANDOM # LOW..HIGH   *
*                              *
* _CMP16 : 16BIT COMPARE       *
* _RND16 : 16BIT RANDOM #      *
* _RNDW : RANDOM WORD LOW..HI  *
* _MUL8 : 8BIT MULTIPLY        *
* _DIV8 : 8BIT DIVIDE, REMAIND *
*                              *
*-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=*
*
*
*``````````````````````````````*
* _ADD16 :: 16-BIT ADDITION    *
*-                            -*
* ADD TWO 16BIT VALUES, STORE  *
* RESULT IN Y, X (LOW, HIGH)   *
*-                            -*
* PARAMETERS:                  *
*                              *
* PARAM1 = ADDEND 1            *
* PARAM2 = ADDEND 2            *
*-                            -*
* SAMPLE USAGE:                *
*                              *
*        _ADD16 #3000;#4000    *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
_ADD16   MAC
         LDA   #>]1
         PHA
         LDA   #<]1
         PHA
         LDA   #>]2
         PHA
         LDA   #<]2
         PHA
         JSR   ADD16
         <<<
*
*``````````````````````````````*
* _SUB16 :: 16-BIT SUBTRACTION *
*-                            -*
* SUBTRACTS ONE 16BIT INTEGER  *
* FROM ANOTHER, STORING THE    *
* RESULT IN Y,X (LOW, HIGH)    *
*-                            -*
* PARAMETERS:                  *
*                              *
* PARAM1 = MINUEND             *
* PARAM2 = SUBTRAHEND          *
*-                            -*
* SAMPLE USAGE:                *
*                              *
*        _SUB16 #2000;#1500    *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
_SUB16   MAC
         LDA   #>]1
         PHA
         LDA   #<]1
         PHA
         LDA   #>]2
         PHA
         LDA   #<]2
         PHA
         JSR   SUB16
         <<<
*
*``````````````````````````````*
* _MUL16 :: 16-BIT MULTIPLY    *
*-                            -*
* MULTIPLIES TWO 16BIT NUMBERS *
* AND RETURNS THE PRODUCT IN   *
* Y,X (LOW, HIGH).             *
*-                            -*
* PARAMETERS:                  *
*                              *
* PARAM1 = MULTIPLICAND        *
* PARAM2 = MULTIPLIER          *
*-                            -*
* SAMPLE USAGE:                *
*                              *
*        _MUL16 #400;#500      *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
_MUL16   MAC
         LDA   #>]1
         PHA
         LDA   #<]1
         PHA
         LDA   #>]2
         PHA
         LDA   #<]2
         PHA
         JSR   MUL16
*
** NOW XFER STACK TO X,Y
*
** REALLY, THIS SHOULD BE IN THE
** ACTUAL ROUTINE. UNNECESSARY CYCLES.
*
** ALSO, HAVE IT RETURN THE 24BIT IN A,
** EVEN THOUGH IT'S CURRENTLY UNRELIABLE
*
         PLA
         TAY
         PLA
         TAX              ; HIGH
         <<<
*
*``````````````````````````````*
* _DIV16 :: 16-BIT DIVISION    *
*-                            -*
* DIVIDES ONE 16BIT NUMBER BY  *
* ANOTHER AND RETURNS THE      *
* RESULT IN Y,X (LOW,HIGH).    *
*                              *
* IF THE THIRD PARAMETER IS    *
* PASSED WITH A U, VALUES WILL *
* BE TREATED AS UNSIGNED; IF   *
* NOT, VALUES WILL BE TREATED  *
* AS SIGNED.                   *
*-                            -*
* PARAMETERS:                  *
*                              *
* PARAM1 = DIVIDEND            *
* PARAM2 = DIVISOR             *
*-                            -*
* SAMPLE USAGE:                *
*                              *
*        _DIV16 #3000;#300     *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
_DIV16   MAC
         LDA   #>]1
         PHA
         LDA   #<]1
         PHA
         LDA   #>]2
         PHA
         LDA   #>]2
         PHA
         IF    U,]3       ; UNSIGNED
         JSR   UDIV16
         ELSE
         JSR   SDIV16     ; SIGNED
         FIN
*
** NOW TRANSFER STACK TO Y,X
*
         PLA
         TAY              ; LOW
         PLA
         TAX              ; HIGH
         <<<
*
*``````````````````````````````*
* _REM16 :: 16-BIT DIV REMAINR *
*-                            -*
* DIVIDES ONE INTEGER BY       *
* ANOTHER AND RETURNS THE      *
* REMAINDER IN Y,X (LOW, HIGH) *
*                              *
* IF THE THIRD PARAMETER IS    *
* PASSED WITH A U, VALUES WILL *
* BE TREATED AS UNSIGNED; IF   *
* NOT, VALUES WILL BE TREATED  *
* AS SIGNED.                   *
*-                            -*
* PARAMETERS:                  *
*                              *
* PARAM1 = DIVIDEND            *
* PARAM2 = DIVISOR             *
*-                            -*
* SAMPLE USAGE:                *
*                              *
*        _REM16 #1000;#333     *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
_REM16   MAC
         LDA   #>]1
         PHA
         LDA   #<]1
         PHA
         LDA   #>]2
         PHA
         LDA   #>]2
         PHA
         IF    U,]3       ; UNSIGNED
         JSR   UREM16
         ELSE
         JSR   SREM16     ; SIGNED
         FIN
*
** TRANSFER STACK TO Y,XX
*
         PLA
         TAY              ; LOW
         PLA
         TAX              ; HIGH
         <<<
*
*``````````````````````````````*
* _RNDB :: 8BIT RANDOM LOW,HI  *
*-                            -*
* RETURNS A RANDOM NUMBER IN   *
* REGISTER A THAT IS BETWEEN   *
* THE LOW AND HIGH BOUNDARIES  *
* PASSED IN THE PARAMETERS.    *
*                              *
* NOTE THAT THIS RETURNS A     *
* BYTE, AND THUS ONLY DEALS    *
* WITH VALUES BETWEEN 0..255.  *
*-                            -*
* PARAMETERS:                  *
*                              *
* PARAM1 = LOW BOUNDARY        *
* PARAM2 = HIGH BOUNDARY       *
*-                            -*
* SAMPLE USAGE:                *
*                              *
*        _RNDB #50;#100        *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
_RNDB    MAC
         LDA   ]1         ; LOW
         PHA
         LDA   ]2         ; HIGH
         PHA
         JSR   RANDB
         <<<
*
*``````````````````````````````*
* _CMP16 : 16BIT COMPARISON    *
*-                            -*
* COMPARES TWO 16BIT VALUES    *
* AND ALTERS THE P-REGISTER    *
* ACCORDINGLY (FLAGS).         *
*-                            -*
* PARAMETERS:                  *
*                              *
* PARAM1 = WORD 1 TO COMPARE   *
* PARAM2 = WORD 2 TO COMPARE   *
*-                            -*
* SAMPLE USAGE:                *
*                              *
*        _CMP16 #1023;#3021    *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
_CMP16   MAC
         LDA   #>]1
         PHA
         LDA   #<]1
         PHA
         LDA   #>]2
         PHA
         LDA   #<]2
         PHA
         JSR   CMP16
         <<<
*
*``````````````````````````````*
* _MUL8 :: 8BIT MULTIPLICATION *
*-                            -*
* MULTIPLIES TWO 8BIT VALUES   *
* AND RETURNS A 16BIT RESULT   *
* IN Y,X (LOW, HIGH).          *
*-                            -*
* PARAMETERS:                  *
*                              *
* PARAM1 = MULTIPLICAND        *
* PARAM2 = MULTIPLIER          *
*-                            -*
* SAMPLE USAGE:                *
*                              *
*         _MUL8 #10;#20        *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
_MUL8    MAC
         LDA   ]1
         PHA
         LDA   ]2
         PHA
         JSR   MUL8
         <<<
*
*``````````````````````````````*
* _DIV8 :: 8BIT MULTIPLICATION *
*-                            -*
* DIVIDES ONE 8BIT NUMBER BY   *
* ANOTHER AND STORES THE       *
* QUOTIENT IN A WITH THE       *
* REMAINDER IN X.              *
*-                            -*
* PARAMETERS:                  *
*                              *
* PARAM1 = DIVIDEND            *
* PARAM2 = DIVISOR             *
*-                            -*
* SAMPLE USAGE:                *
*                              *
*        _DIV8 #100;#10        *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
_DIV8    MAC
         LDA   ]1
         PHA
         LDA   ]2
         PHA
         JSR   DIV8
         <<<