非接触式智能卡模块ID-0/10/15的原理及应用

WIEGAND_DATA: RLC A ;

DJNZ R3,WIEGAND1 ;BYTE IS NOT OVER

ANL A,#00001111B ;BYTE OVER

MOV @R0,A ;SAVE DATA TO INRAM

INC R0 ;INCREASE INRAM ADDRESS

MOV R3,#4 ;4 BITS PER BYTE

DJNZ R2,WIEGAND1 ; READ DATA AGAIN

ODD: JNB ID-0_DATA0,ODD_BIT ;WAIT ODD CHECK BIT

JB ID-0_DATA1,ODD ;

ODD_BIT: NOP ;

LCALL DELAY25US ;DELAY 25 μS

MOV C,ID-0_DATA0 ;ODD CHECK BIT

MOV ODD_CHECK,C ;SAVE ODD CHECK BIT

NOP

LJMP OTHER_PROGRAM ;READ CARD OVER

DELAY25US: MOV R4,#11 ;DELAY 25μS

DELAY25US_A: DJNZ R4,DELAY25US_A

NOP

RET

DELAY175US: MOV R4,#86 ;DELAY 175 μS

DELAY175US_A: DJNZ R4,DELAY175US_A