【正文】 D2 。計(jì)算完十六位商（R4R5）MOV A,R4 。將商移到R2R3中MOV R2,AMOV A,R5MOV R3,ACLR OV 。設(shè)立成功標(biāo)志RET。============================================。（１７） 標(biāo)號： ＨＢ２ 功能：雙字節(jié)十六進(jìn)制整數(shù)轉(zhuǎn)換成雙字節(jié)ＢＣＤ碼整數(shù)。入口條件：待轉(zhuǎn)換的雙字節(jié)十六進(jìn)制整數(shù)在RR7中。出口信息：轉(zhuǎn)換后的三字節(jié)ＢＣＤ碼整數(shù)在RRR5中。影響資源：PSW、A、R2～R7 堆棧需求： ２字節(jié)HB2: CLR A 。ＢＣＤ碼初始化MOV R3,AMOV R4,AMOV R5,AMOV R2,10H 。轉(zhuǎn)換雙字節(jié)十六進(jìn)制整數(shù)HB3: MOV A,R7 。從高端移出待轉(zhuǎn)換數(shù)的一位到CY中RLC AMOV R7,AMOV A,R6RLC AMOV R6,AMOV A,R5 。ＢＣＤ碼帶進(jìn)位自身相加，相當(dāng)于乘２ADDC A,R5DA A 。十進(jìn)制調(diào)整MOV R5,AMOV A,R4ADDC A,R4DA AMOV R4,AMOV A,R3ADDC A,R3MOV R3,A 。雙字節(jié)十六進(jìn)制數(shù)的萬位數(shù)不超過６，不用調(diào)整DJNZ R2,HB3 。處理完１６ｂｉｔRET。===================================。24c02存儲器的使用。**********開始STA: SETB SETB NOP NOP CLR NOP NOP CLR RET。**********停止STOP: CLR SETB NOP NOP SETB NOP NOP CLR RET。**********發(fā)送應(yīng)答MACK: CLR SETB NOP NOP CLR SETB RET。*********發(fā)送非應(yīng)答MNACK: SETB SETB NOP NOP CLR CLR RET。**********應(yīng)答位檢查CACK: SETB SETB CLR F0 NOP MOV A,P1 NOP NOP JNB ,CEND SETB F0CEND: CLR NOP RET。**********寫入一個(gè)字節(jié)WRBYT: MOV R0,08HWLP: RLC A JC WR1A AJMP WR0WLP1: DJNZ R0,WLP RETWR1A: SETB SETB NOP NOP CLR CLR AJMP WLP1WR0: CLR SETB NOP NOP CLR AJMP WLP1。**********讀出一個(gè)字節(jié)RDBYT: MOV R0,08HRLP: SETB SETB MOV A,P1 JNB ,RD0 AJMP RD1RLP1: DJNZ R0,RLP RETRD0: CLR C MOV A,R2 RLC A MOV R2,A CLR AJMP RLP1RD1: SETB C MOV A,R2 RLC A MOV R2,A CLR AJMP RLP1。**********寫入多個(gè)字節(jié)WRNBYT: PUSH PSW MOV PSW,18H LCALL STA MOV A,0A0H 。SLA LCALL WRBYT LCALL CACK JB F0,WRNBYT MOV A,00H 。SLA LCALL WRBYT LCALL CACK JB F0,WRNBYT MOV R1,30H 。MTDWRDAA: MOV A,@R1 LCALL WRBYT LCALL CACK JB F0,WRNBYT INC R1 DJNZ 2FH,WRDAA LCALL STOP MOV 2FH,08H POP PSW RET。**********讀出多個(gè)字節(jié)RDNBYT: PUSH PSW MOV PSW,18H LCALL STA MOV A,0A1H 。SLA LCALL WRBYT LCALL CACK JB F0,RDNBYTRDN: MOV R1,40H 。MRDRDN1: LCALL RDBYT MOV @R1,A DJNZ 2FH,ACK LCALL MNACK LCALL STOP MOV 2FH,08H POP PSW RETACK: LCALL MACK INC R1 SJMP RDN1。===========================DELAY: MOV R6,04DL2: MOV R5,250DL3: MOV R4,249 DJNZ R4,$ DJNZ R5,DL3 DJNZ R6,DL2 NOP RETDELAY1: MOV R6,01HDL12: MOV R5,1FHDL13: MOV R4,0FFH DJNZ R4,$ DJNZ R5,DL13 DJNZ R6,DL12 NOP RET 。********** 。讀字節(jié)首地址 。**********LLL: PUSH PSW MOV PSW,18H LCALL STA MOV A,0A0H 。SLA LCALL WRBYT LCALL CACK JB F0,LLL MOV A,00H LCALL WRBYT LCALL CACK JB F0,LLL POP PSW RET27 / 12