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Added putder() to stdiox.a02

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Curtis F Kaylor
2018-02-02 18:02:06 -05:00
parent c3cc4be48c
commit a1294860cd
3 changed files with 130 additions and 21 deletions
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include/stdlib.a02
+35 -21
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@@ -123,39 +123,54 @@ ATOCL: LDA (SRCLO),Y ;Get Next Character
ATOCX: LDA TEMP0 ;Load Result
RTS ;And Return
;Convert Byte to ASCII
;Convert Byte to ASCII String
;Uses SRCLO, srchi, TEMP0, TEMP1, TEMP2
;Affects A,X,Y,N,Z
CTOA: JSR SETSRC ;Initialize Source String
JSR CVBCD ;Convert Accumulator to BCD
;LDY #$00 ;Set String Offset to 0
CTOA: JSR SETSRC ;Initialize Source String
JSR CUBCD ;Convert Accumulator to Unpacked BCD
LDA TEMP2 ;Get High Byte
BEQ CTOAL ;If Not Zero
BEQ CTOA1 ;If Not Zero
JSR CTOAN ; Convert Low Nybble
CTOAL: LDA TEMP1 ;Get Low Byte
CTOA1: LDA TEMP1 ;Get Low Byte
BNE CTOA2 ;If Not Zero
CMP TEMP2 ; and Hundreds
BEQ CTOA3 ; not Zero
CTOA2: JSR CTOAN ; Convert It
CTOA3: LDA TEMP0 ;Get Low Byte
JSR CTOAN ;and Convert Low Nybble
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
INY ;and Increment Offset
RTS
;Unpack 3-Digit BCD Number
;Input: TEMP1 = Low Byte
; TEMP2 = High Nybble
;Output: TEMP0 = Ones Digit
; TEMP1 = Tens Digit
; TEMP2 = Hundreds Digit
;Affects: A,N,Z
;Returns: X = 0
CUBCD: JSR CVBCD ;Convert Accumulator to BCD
UPBCD: LDA TEMP1 ;Get Low Byte
AND #$0F ;Strip High Nybbleet
STA TEMP0 ;Save in Ones
LDA TEMP1 ;Get Low Byte
LSR ;Shift High Nybble
LSR ; into Low Nybble
LSR
LSR
BNE CTOA2 ;If Not Zero
CMP TEMP2 ; and High Byte
BEQ CTOA3 ; not Zero
CTOA2: JSR CTOAN ; Convert It
CTOA3: LDA TEMP1 ;Get Low Byte
JSR CTOAN ;and Convert Low Nybble
LDA #$00
BEQ CTOAX ;Terminate String
CTOAN: AND #$0F ;Strip High Nybble
ORA #$30 ;Convert to ASCII digit
CTOAX: STA (SRCLO),Y ;Store in String
INY ;and Increment Offset
STA TEMP1 ;Save in Tens
RTS
;Convert Binary Number in Accumulator to Binary Coded Decimal
;Uses TEMP0
;Uses: TEMP0
;Returns BCD in TEMP1,temp and A,X = 0
CVBCD: STA TEMP0 ;Save Binary Value
LDA #0 ;Clear BCD Bytes
CVBCDT: LDA #0 ;Clear BCD Bytes
STA TEMP1
STA TEMP2
LDX #8 ;Process 8 bits of Binary
@@ -173,4 +188,3 @@ CVBCDL: ASL TEMP0 ;Shift High Bit Into Carry
CLD ;Clear Decimal Mode
CLI ;Enable Interrupts
RTS