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; [2 bytes hexadecimal to 5 decimal]
; FlameCyclone 2017.6.11


 .ORG $8000
 
HEX_D = $70
DEC_D = $72
 
HEX_TO_DEC:        ; Hexadecimal to decimal
 PHA        ; protects current A and X data
 TXA
 PHA
 LDA #$FF
 STA HEX_D        ; sets the high order of the hexadecimal number to be converted
 LDA #$FF
 STA HEX_D + 1        ; Sets the low bit of the hexadecimal number to be converted
 JSR DEC_CLEARN        ; Clear the decimal data
 JSR TS_D        ; Hexadecimal to decimal
 PLA        ; recovery before A and X data
 TAX
 PLA
 RTS        ; return

HEX_DEC_DATA_H: Decimal corresponding hexadecimal high
 .DB $27
 .DB $03
 .DB $00
 .DB $00
 .DB $00
 
HEX_DEC_DATA_L: Decimal corresponding hexadecimal low
 .DB $10
 .DB $E8
 .DB $64
 .DB $0A
 .DB $01
 
DEC_CLEARN:        ; Clears the decimal data
 LDX #$00
 LDA #$00
 STA DEC_D
 STA DEC_D + 1
 STA DEC_D + 2
 STA DEC_D + 3
 STA DEC_D + 4
 RTS
 

TS_D:        ; Hexadecimal conversion to decimal data
 LDA HEX_D        ; Reads the hexadecimal digits to be converted
 CMP HEX_DEC_DATA_H, X        ; High conversion of hexadecimal number to decimal number corresponding to decimal number
 BNE TS_D_S        ; does not have the same conversion
 LDA HEX_D + 1        ; Read the decimal number to be converted to hexadecimal
 CMP HEX_DEC_DATA_L, X        ; ​​the high level of the hexadecimal number to be converted to the decimal number corresponding to the decimal number
 BCC TS_D_RTS        ; less than the current decimal not converted
TS_D_S:        ; The conversion is started
 LDA HEX_D        ; Reads the hexadecimal digits to be converted
 CMP HEX_DEC_DATA_H, X        ; High conversion of hexadecimal number to decimal number corresponding to decimal number
 BCC TS_D_RTS        ; less than the current decimal not converted
 LDA HEX_D + 1        ; Read the decimal number to be converted to hexadecimal
 SEC        ; entry position 1
 SBC HEX_DEC_DATA_L, X        ; ​​Low conversion of hexadecimal number to decimal place corresponding to decimal number
 STA HEX_D + 1        ; the result is sent to the lower hexadecimal number to be converted
 BCS D_DEC_HEX_D        ; skip without borrow
 DEC HEX_D        ; there is a borrow to convert hexadecimal highs
D_DEC_HEX_D:        ; Hexadecimal highs decrease
 LDA HEX_D        ; Reads the hexadecimal digits to be converted
 SEC        ; entry position 1
 SBC HEX_DEC_DATA_H, X        ; High conversion of hexadecimal digits to decimal places corresponding to decimal
 STA HEX_D        ; the result is sent to the hexadecimal number to be converted
ADD_DEC_D:        ; Decimal corresponding bit increments
 INC DEC_D, X        ; Decimal corresponding bit increments
 JMP TS_D        ; continue conversion
TS_D_RTS:        ; Converts a decimal bit to the end
 INX        ; counter increments
 CPX #$05        ; whether to convert 5 number
 BCC TS_D        ; continue to convert the next bit without conversion
 RTS        ; return [/ code]