How to interface TLC 0831 with 8051 in Assembly?

AD_CS BIT P1.0             ;CS, CK and DO fitted to port 1
AD_CK BIT P1.1
AD_DO BIT P1.2
AD_RESULT equ 030h;        ;This variable holds result from A/D conversion.
;
    		MOV P1, 0FFh
    		CLR AD_CK
    		CLR AD_CS      ;Select chip (initiate conversion)
;    
    		MOV R1, #02h
;
PREPARE:    SETB AD_CK     ;MUX settling time
    		ACALL delay_us
    		CLR AD_CK
    		ACALL delay_us
    		DJNZ R1, PREPARE
    
    		MOV R2,AD_RESULT
    		MOV R1, #08h    ;Read in value from A/D convertor, 8 BITS
CONVERSION: SETB AD_CK
        	ACALL delay_us
        	MOV C, AD_DO
        	MOV A, R2
        	RLC A           ;Left because MSB comes in first
        	MOV R2, A
        	CLR AD_CK
        	ACALL delay_us
    		DJNZ R1, CONVERSION
    		MOV AD_RESULT, R2
    
    		SETB AD_CK       ;cycle clock once.
    		ACALL delay_us;
    		CLR AD_CK
    		ACALL delay_us;

    		SETB AD_CS       ;Deselect chip.

delay_us:                    ;FOR STANDARD 12 CYCLE and 11.0592 MHz
			MOV R3, #05h      ;10 uS
			DJNZ R3, $
			RET