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Added module intlib and updated module stdiox
This commit is contained in:
Curtis F Kaylor
parent
71e15fb2d8
commit
0bd11dbaed
244
include/intlib.a02
Normal file
244
include/intlib.a02
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@ -0,0 +1,244 @@
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; C02 library stdlib.h02 assembly language subroutines
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; Requires
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; external zero page locations SRCLO and SRCHI
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; and external locations RANDOM, RDSEED, TEMP0, TEMP1, and TEMP2.
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;iabs(n) - Get Integer ABSolute Value
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;Args: Y,X = Integer to get Absolute Value Of
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;Sets: TEMP1, TEMP2
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;Affects: C, N, Z
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;Returns: A = Absolute Value of Argument
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IABS: CPY #$80 ;If Negative (High Bit Set)
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BCC IABSX ; Carry will Already be Set
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JSR SAVRXY ; Copy LSB, MSB to TEMP1. TEMP2
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LDA #0 ; Subtract LSB
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SBC TEMP1 ; from 0
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TAX ; and Copy to X Register
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LDA #0 ; Subtract MSB
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SBC TEMP2 ; from 0
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TAY ; and Copy to Y Register
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IABSX: RTS
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;imax(m,n) - Get MAXimum of Two Integers
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;Args: A,Y = Numbers to Compare
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;Affects: N,Z,C
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;Returns: A = Larger of the Two Arguments
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IMAX: CPY SRCHI ;If Y < SRCHI
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BCC IMAXC ; Return SRCLO, SRCHI
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CPX SRCLO ;IF X >= SRCLO
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BCS IMINX ; Return Argument
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IMAXC: JMP GETSRC ;Return Integer in SRCLO, SRCHI
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;imin(m,n) - Get MINimum Get MAXimum of Two Numbers
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;Args: A,Y = Numbers to Compare
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;Sets: TEMP0 = Second Argument
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;Affects: N,Z,C
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;Returns: A = Smaller of the Two Arguments
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IMIN: CPY SRCHI ;If Y < SRCHI
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BCS IMINX ; Return Argument
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BNE IMAXC ;If Y > SRCHI Return SRCHI,SRCLO
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CPX SRCLO ;If X < SRCLO
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BCS IMINX ; Return Argument
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BNE IMAXC ;If X > SRCLO Return SRCHI,SRCLO
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IMINX: RTS ;Return Argument
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;iadd(d) - ADD Integer d to from Integer g
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;Args: Y,X = Addend
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;Requires: setsrc(g) - Augend
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;Sets: TEMP1,TEMP2 = Addend
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;Affects: Z,C
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;Returns: A = Sum (Bits 16-23)
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; Y,X = Sum (Bits 0-15)
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; N = Sign of Result
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IADD: CLC ;Clear Carry for Addition
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TXA ;Add Addend LSB
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ADC SRCLO ;to Augend LSB
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TAX ;and Copy to X
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TYA ;Add Addend MSB
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ADC SRCHI ;to Augebd MSB
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TAY ;and Copy to Y
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LDA #0 ;Set Overflow to 0
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ROL ; Rotate Carry (Same as Adding it)
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RTS ; and Return
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;isub(s) - SUBtract Integer s from Integer m
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;Args: Y,X = Subtrahend
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;Requires: setsrc(m) - Minuend
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;Sets: TEMP1,TEMP2 = Subtrahend
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;Affects: Z,C
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;Returns: A = Differencee (Bits 16-23)
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; Y,X = Difference (Bits 0-15)
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; N = Sign of Result
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ISUB: JSR SAVRXY ;Store Subtrahend in TEMP1,TEMP2
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SEC ;Set Carry for Subtraction
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LDA SRCLO ;Load Minuend LSB
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SBC TEMP1 ;Subtract Subtrahend LSB
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TAX ;Copy Difference LSB to X
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LDA SRCHI ;Load Minuend MSB
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SBC TEMP2 ;Subtract Subtrahend MSB
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TAY ;Copy Difference MSB to Y
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LDA #0 ;Set Overflow Byte to 0
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SBC #0 ; Subtract Carry
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RTS ; and Return
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;imult(m) - MULTiply Two Integers
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IMULT: RTS
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;idiv(d) - MULTiply Two Numbers
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IDIV: RTS
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;ishftl(n,i) - Shift Integer i to the Left n Bits
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;Sets: TEMP1, TEMP2 = LSB, MSB of Result
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;Affects: A,Y,N,Z,C
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;Returns: Y,X = Shifted Integer
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ISHFTL: JSR SAVRXY ;Save X,Y in TEMP1,TEMP2
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TYA ;Set Counter to Number of Bits
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ASL TEMP1 ;Shift LSB to Left
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ROL TEMP2 ;Rotate MSB to Left
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DEY ;Decrement Counter
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BNE ISHFTL ; and Loop if Not 0
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BEQ ISHFTX ;Return Shifted Integer
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;ishftr(n,i) - Shift Integer i to the Right n Bits
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;Sets: TEMP1, TEMP2 = LSB, MSB of Result
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;Affects: A,Y,N,Z,C
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;Returns: Y,X = Shifted Integer
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ISHFTR: JSR SAVRXY ;Save X,Y in TEMP1,TEMP2
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TYA ;Copy
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LSR TEMP1 ;Shift LSB to Right
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ROR TEMP2 ;Rotate MSB to Right
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DEY ;Decrement Counter
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BNE ISHFTR ; and Loop if Not 0
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ISHFTX: JMP RESRXY ;Load Shifted Integer and Return
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;atoi(&s) - ASCII string TO Integer
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;Args: Y,X = Address of String to Convert
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;Sets: TEMP1, TEMP2 = Integer Value
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;Affects: TEMP0
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;Returns: A = Number of Digits
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; Y,X = Integer Value
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ATOI: JSR SETSRC ;Initialize Source String
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STY TEMP1 ;Initialize Result
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STY TEMP2
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ATOIL: LDA (SRCLO),Y ;Get Next Character
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CMP #$30 ;If Less Than '0'
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BCC ATOIX ; Exit
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CMP #$3A ;If Greater Than '9'
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BCS ATOIX ; Exit
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AND #$0F ;Convert to Binary Nybble
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STA TEMP0 ; and Save It
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LDA TEMP1 ;Load Result
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LDX TEMP2
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ASL TEMP1 ;Multiply by 5 by
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ROL TEMP2
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ASL TEMP1 ; Multiplying by 4
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ROL TEMP2
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CLC ; And Adding Itself
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ADC TEMP1
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STA TEMP1
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TXA
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ADC TEMP2
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STA TEMP2
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ASL TEMP1 ;Multiply that by 2
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ROL TEMP2
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LDA TEMP0 ;Get Saved Nybble
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CLC ;and Add to Result
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ADC TEMP1 ;Add Saved Nybble
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STA TEMP1 ; and Store Result
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LDA #0
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ADC TEMP2
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STA TEMP2
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INY ;Increment Index
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BPL ATOIL ; and Loop
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ATOIX: TYA ;Return Number of Digits
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JMP RESRXY ;and Integer Value
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;itoa(n) - Integer TO ASCII string
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;Args: Y,X = Integer Value to Convert
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;Uses: DSTHI,DSTLO = Destination String
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;Returns: A,Y = Length of String
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ITOA: JSR CVIBCD ;Convert Integer to Packed BCD
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LDY #0 ;Initialize Index into String
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STY TEMP3
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ITOAA: LDY #4 ;Set Initial Digit Number
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JSR UPBCDI ;Unpack Digit Y
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ITOAZ: BNE ITOAS ;If Zero
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DEX ; Decrement Digit Number
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BNE ITOAZ ; If Not Zero Loop
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BEQ ITOAS ; Else Skip Unpack
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ITOAL: JSR UPBCDI ;Unpack Digit #Y
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ITOAS: TAX ;Save Digit in X
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TYA ;Push Digit Number into Stack
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PHA
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TXA ;and Restore Digit
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LDY TEMP3 ;Get Index into String
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ORA #$30 ;Convert Digit to ASCII
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STA (DSTLO),Y ;and Store in String
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INC TEMP3 ;Increment Index into String
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PLA ;Pull Digit Number off Stack
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TAY
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DEY ;Decrement Digit Number
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BPL ITOAL ;Loop if >= Zero
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LDA #0 ;Terminate String
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STA (DSTLO),Y
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TYA ;Return String Length
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RTS
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;upbcdi() - UnPack digits from BCD Integer
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; Assumes that TEMP0, TEMP1, and TEMP2
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; are in consecutive memory locations
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;Args: Y = Digit Number to Unpack (0-5)
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;Uses: TEMP0 = Low Byte
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; TEMP1 = Middle Byte
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; TEMP2 = High Nybble
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;Affects: X,C,N,Z
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;Returns: A = Unpacked Digit
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UPBCDI: TYA ;Divide Digit Number by 2,
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LSR ; Setting Carry
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TAX ; if Digit Number is Odd
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LDA TEMP0,X ;Load BCD Byte
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BCC UPBCDS ;If Digit Number is Odd
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LSR ;Shift High Nybble to Low Nybble
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LSR
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LSR
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LSR
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UPBCDS: AND #$0F ;Strip Off High Nybble
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RTS
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;cvibcd(int) - ConVert Integer to packed Binary Coded Decimal
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;Args: Y,X - Integer to Convert
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;Sets: TEMP0 = Tens and Ones Digit
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; TEMP1 = Hundreds Digit
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; TEMP2 = Thousands Digit
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;Affects: A,X,Y
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CVIBCD: LDA #0 ;Clear BCD Bytes
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STA TEMP0
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STA TEMP1
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STA TEMP2
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PHP ;Save Status Register
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SEI ;Disable Interrupts
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SED ;Set Decimal Mode
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TYA ;Push MSB onto Stack
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PHA
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TXA ;Push LSB onto Stack
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PHA
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TSX ;Copy Stack Pointer to X
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LDY #16 ;Process 16 bits of Binary
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CVIBCL: ASL $101,X ;Shift High Bit Into Carry
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ROL $102,X
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LDA TEMP0 ;Add 6 Digit BCD Number Itself
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ADC TEMP0 ; Effectively Multiplying It by 2
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STA TEMP0 ; and Adding in the Shifted Out Bit
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LDA TEMP1
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ADC TEMP1
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STA TEMP1
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LDA TEMP2
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ADC TEMP2
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STA TEMP2
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DEY ;Decrement Counter and
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BNE CVIBCL ; Process Next Bit
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PLA ;Restore Stack
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PLA
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PLP ;Restore Status Register
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RTS
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70
include/intlib.h02
Normal file
70
include/intlib.h02
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@ -0,0 +1,70 @@
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/*********************************************************
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* intlib - Standard Library Routines for Integer Values *
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*********************************************************/
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/* Absolute Value *
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* Args: w - Word to get absolute value of *
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* Returns: (int) Absolute value of w */
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char iabs();
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/* Add Integers *
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* Requires: setsrc(g) - Augend *
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* Args: d - Addend *
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* Returns: (int) Sum */
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char iadd();
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/* Convert ASCII String to Unsigned Integer *
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* Args: &s - String to Convert *
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* Returns: (char) Number of digits parsed *
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* (int) Numeric value of string */
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char atoi();
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/* Convert Unsigned Integer to ASCII String *
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* Requires: setdst(s) - Destination String *
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* Args: w - Unsigned Byte to Convert *
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* Returns: Length of string */
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void itoa();
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/* Divide Unsigned Integers *
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* Requires: setsrc(n) - Numerator *
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* Args: d - Denominator *
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* Returns: (int) Quotient */
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char idiv();
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/* Maximum of Two Integers *
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* Requires: setsrc(i) - First Integer *
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* Args: j - Second Integer *
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* Returns: (int) Greater of the Two */
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char max();
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/* Minimum of Two Integers *
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* Requires: setsrc(i) - First Integer *
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* Args: j - Second Integer *
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* Returns: (int) Lesser of the Two */
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char min();
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/* Multiply Unsigned Integers *
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* Requires: setsrc(m) - Muliplicand *
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* Args: r - Multiplier *
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* Returns: (char) Product (Bits 16-23) *
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* (int) Product (Bits 0-15) */
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char mult();
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/* Shift Integer Left *
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* Args: n - Number of Bits to Shift *
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* w - Integer Value to Shift *
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* Returns: Shifted Integer */
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char ishftl();
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/* Shift Byte Right *
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* Args: n - Number of Bits to Shift *
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* w - Integer Value to Shift *
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* Returns: Shifted Integer */
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char ishftr();
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/* Subtract Integers *
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* Requires: setsrc(m) - Minuend *
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* Args: s - Subtrahend *
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* Returns: (int) Difference */
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char isub();
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@ -63,3 +63,37 @@ GETSRC: LDX SRCLO
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LDY SRCHI
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RTS
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;Add Accumulator to Destination Address
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ADDDSA: TAX ;Move Accumulator to Argument LSB
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LDY #0 ;Clear Argument MSB
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;Add to Destination Address
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;Args: Y,X = MSB,LSB of Integer to Add
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;Affects: A,Y,X
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ADDDST: LDA #DSTLO ;Set Index to Destination Pointer
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BNE ADDZPW ;and Execute ADDZPW
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;Add Accumulator to Source Address
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ADDSRA: TAX ;Move Accumulator to Argument LSB
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LDY #0 ;Clear Argument MSB
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;Add to Source Address
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;Args: Y,X = MSB,LSB of Integer to Add
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;Affects: A,Y,X
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ADDSRC: LDA #SRCLO ;Set Index and Drop into ADDZPW
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;Add to Zero Page Word
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;Args: A = Address of Zero Page Word
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; Y,X = MSB,LSB of Integer to Add
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;Affects: A
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ADDZPW: STA TEMP3 ;Save Zero Page Address
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TXA ;Move Argument LSB to Accumulator
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LDX TEMP3 ;Set Index to Zero Page Address
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CLC ;Clear Carry
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ADC 0,X ;Add Argument LSB to Target LSB
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STA 0,X ;and Save Result
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TYA ;Move Argument MSB to Accumulator
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ADC 1,X ;Add Argument MSB to Target MSB
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STA 1,X ;and Save Result
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RTS
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@ -6,6 +6,19 @@
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#define TRUE $FF
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#define FALSE $00
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/* Add to Destination Pointer *
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* Args: &n - amount to add */
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void adddst();
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/* Add to Source Pointer *
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* Args: &n - amount to add */
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void addsrc();
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/* Add to Zero Page Word *
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* Args: z - Zero page address *
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* &n - amount to add */
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void addzpw();
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/* Get Destination Pointer *
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* Returns: Y,X=Destination address */
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int getdst();
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@ -61,3 +74,4 @@ void setsrc();
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/* Set Source Pointer to Destination Pointer */
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void setsrd();
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@ -38,7 +38,7 @@ PUTBIL: LDA #0
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ASL TEMP0 ;Shift Top Bit Out
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ADC #$30 ;Convert to '0' or '1'
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JSR PUTCHR ;Print Digit
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DEX ;Decremebt Index
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DEX ;Decrement Index
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BNE PUTBIL ;Loop if Not Done
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RTS
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@ -80,20 +80,33 @@ PUTDES: JSR PUTDEH
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PUTDEC: JSR CUBCD ;Convert Accumulator to Unpacked BCD
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LDA TEMP2 ;Get High Byte
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BEQ PUTDE1 ;If Not Zero
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JSR PUTDEP ; Convert Low Nybble
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JSR PUTDGT ; Print Digit
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PUTDE1: LDA TEMP1 ;Get Low Byte
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BNE PUTDE2 ;If Not Zero
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CMP TEMP2 ; and Hundreds
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BEQ PUTDE3 ; not Zero
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PUTDE2: JSR PUTDEP ; Convert It
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PUTDE2: JSR PUTDGT ; Print Digit
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PUTDE3: LDA TEMP0 ;Get Low Byte
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PUTDEP: ORA #$30 ;Convert to ASCII digit
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JSR PUTCHR ;And Print
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RTS
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PUTDGT: ORA #$30 ;Convert to ASCII digit
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JMP PUTCHR ;And Print
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;puthex(&word) - PUT HEXadecimal
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PUTHEX EQU PRBYTE ;Print Byte as Hexadecimal
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;putint(&word) - PUT INTeger
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PUTINT: JSR CVIBCD ;Convert Integer to Packed BCD
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LDY #4 ;Set Initial Digit Number
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JSR UPBCDI ;Unpack Digit X
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PUTINZ: BNE PUTINS ;If Zero
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DEY ; Decrement Digit Number
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BNE PUTINZ ; If Not Zero Loop
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BEQ PUTDGT ; Else Print Digit and Return
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PUTINL: JSR UPBCDI ;Unpack Digit X
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PUTINS: JSR PUTDGT ;Print Digit
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DEY ;Decrement Digit Number
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BPL PUTINL ;Loop if >= Zero
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RTS
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;putwrd(&word) - PUT WoRD
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;Args: Y = Word MSB
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; X = Word LSB
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@ -174,12 +187,21 @@ PRINTS: CMP #'S ;'Else If "s" or "S"
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LDY TEMP0 ; Restore Index
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JMP PRINTY ;
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PRINTW: CMP #'W ;'Else If "w" or "W"
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BNE PRINTZ
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BNE PRINTI
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STY TEMP0 ; Save Index
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JSR SAVDST ; Save Destination Address
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JSR PUTWRA ; Print MSB and LSB as Hex
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LDY TEMP0 ; Restore Index
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JMP PRINTY ;
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PRINTI: CMP #'I ;'Else If "i" or "I"
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BNE PRINTZ
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TYA ; Save Index
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PHA
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JSR GETDST ; Get Integer in DSTLO, DSTHI
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JSR PUTINT ; Print Integer as Decimal
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PLA ; Restore Index
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TAY
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JMP PRINTY ;
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PRINTZ: LDA TEMP3 ;Else
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JMP PRINTC ; Print Raw Byte and Continue
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@ -43,3 +43,18 @@ void puthex();
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/* Print a Space Character */
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void putspc();
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/* Print /* Print Byte as Hexadecimal Number *
|
||||
* Args: b - Number to print */
|
||||
void puthex();
|
||||
|
||||
/* Print Byte as Hexadecimal Number *
|
||||
* Args: b - Number to print */
|
||||
void puthex();
|
||||
|
||||
/* Print Byte as Hexadecimal Number *
|
||||
* Args: b - Number to print */
|
||||
void puthex();
|
||||
|
||||
/* Print Word as Hexadecimal Number *
|
||||
* Args: int w - Number to print */
|
||||
void putwrd();
|
||||
|
||||
@ -151,13 +151,14 @@ ATOCX: LDA TEMP0 ;Load Result
|
||||
|
||||
;ctoa(n) - Character TO ASCII string
|
||||
;Args: Y,X = Address of String to Populate
|
||||
;Sets: SRCLO, SRCHI = Address of String
|
||||
;Sets: DSTLO, DSTHI = Address of String
|
||||
; TEMP0 = Ones Digit
|
||||
; TEMP1 = Tens Digit
|
||||
; TEMP2 = Hundreds Digit
|
||||
;Affects: C,N.Z
|
||||
;Returns: A,Y = Length of String
|
||||
CTOA: JSR SETSRC ;Initialize Source String
|
||||
CTOA: JSR SETDST ;Initialize Source String
|
||||
LDY #0 ;Initialize Index into String
|
||||
JSR CUBCD ;Convert Accumulator to Unpacked BCD
|
||||
LDA TEMP2 ;Get MSB
|
||||
BEQ CTOA1 ;If Not Zero
|
||||
@ -172,7 +173,7 @@ CTOA3: LDA TEMP0 ;Get Low Byte
|
||||
LDA #$00
|
||||
BEQ CTOAX ;Terminate String
|
||||
CTOAN: ORA #$30 ;Convert to ASCII digit
|
||||
CTOAX: STA (SRCLO),Y ;Store in StringCTOAS: STA (SRCLO),Y ;Store in String
|
||||
CTOAX: STA (DSTLO),Y ;Store in String
|
||||
INY ;and Increment Offset
|
||||
TYA ;Copy String Length to Accumulator
|
||||
RTS
|
||||
@ -214,7 +215,7 @@ CVBCDT: LDA #0 ;Clear BCD Bytes
|
||||
PHP ;Save Status Register
|
||||
SEI ;Disable Interupts
|
||||
SED ;Set Decimal Mode
|
||||
CVBCDL: ASL TEMP0 ;Shift High Bit Into Carry
|
||||
CVBCDL: ASL TEMP0 ;Shift High Bit into Carry
|
||||
LDA TEMP1 ;Add BCD Low Byte to Itself
|
||||
ADC TEMP1 ; Plus Bit Shifted out of Binary
|
||||
STA TEMP1 ; Effectively Multiplying It by 2
|
||||
|
||||
Loading…
Reference in New Issue
Block a user