CJNE A, #SENT_STR, CARD_RD6 ; is it the start sentinel? ; MOV R1, #0 ; set counter for the digit number CALL PUT_DIG ; store the start sentinel as first digit INC R1 ; bump up the digit number ; MOV R2, B ; set R2 to number of digits to fetch DEC R2 CARD_RD5_LP: CALL GET_CODE_F ; get next code to A JNB P, CARD_RD6 ; check the parity and if bad try rev reading ANL A, #00FH ; mask the code CJNE A, #SENT_END, CARD_RD5C ; code is not the end code ; CJNE R2, #2, $+3 ; if remaining digit count is >= 2 then trim JC CARD_RD5C ; if came too close to end so use residual count MOV R2, #2 ; trim total count of digits to 2 more ; CARD_RD5C: CALL PUT_DIG ; store the digit in the list