Äî îïåðàöèè MOVL (R0),(R2)+

                                                                        R0 = 00001000

                                                                        R2 = 00001050

                                                          (00001000) = 000000AC          (R3)

                                                          (00001050) = 00000000           (R2)

Ïîñëå...

                                                                        R0 = 00001000

                                                                        R2 = 00001054           <—— Óâåëè÷èëîñü íà 4

                                                          (00001000) = 000000AC

                                                          (00001050) = 000000AC

Êàê âèäíî ïðîèçîøëà ïåðåñûëêà ÷èñëà èç ÿ÷åéêè 00001000 â 00001050 è çíà÷åíèå ðåãèñòðà R2 óâåëè÷èëîñü íà 4. ( Èíñòðóêöèÿ MOVL ïåðåñûëàåò äâîéíûå ñëîâà. Îá ýòîì ãîâîðèò ñóôôèêñ 'L' - Long - äëèííîå èëè äâîéíîå ñëîâî. Ïîýòîìó R2 óâåëè÷èëñÿ íà 4. Âîîáùå ïðåäóñìîòðåíû îïåðàöèè ðàáîòàþùèå ñ áàéòàìè, ñëîâàìè, äâîéíûìè ñëîâàìè è èíîãäà ñ ó÷åòâåðåííûìè ñëîâàìè è èìåþùèå ñóôôèêñû B,W,L è Q ñîîòâåòñòâåííî.)

2.4  ÐÅÆÈÌ Ñ ÀÂÒÎÓÌÅÍÜØÅÍÈÅÌ

            Ýòîò ðåæèì èäåíòè÷åí ðåæèìó ñ àâòîóâåëè÷åíèåì, îäíàêî çäåñü ïîñëå âûïîëíåíèÿ îïåðàöèè ñëåäóåò íå óâåëè÷åíèå, à óìåíüøåíèå îïåðàíäà ïî òåì æå ïðàâèëàì. Äëÿ ïðèìåðà ðàññìîòðèì êîìàíäó CLRB -(R5), êîòîðàÿ â ïàìÿòè áóäåò âûãëÿäåòü êàê 94 75. Çäåñü 94 - êîä îïåðàöèè, à 75 - çíà÷èò: èñïîëüçîâàòü ðåãèñòð R5 ( ?5 ) è ïðîèçâåñòè óìåíüøåíèå ïîñëå èñïîëíåíèÿ ( 7? ).

Äî îïåðàöèè CLRB -(R5)

                                                                        R5 = 00001000

                                                        (00000FFF) = 0000001A

                                                        (000001000) = 0000001A           (R5)

Ïîñëå...

                                                                        R5 = 00000FFF           <——  óìåíüøèëîñü íà 1

                                                         (00000FFF) = 0000001A           (R5)

                                                         (000001000) = 00000000          <——  0

Èçìåíåíèÿ õîðîøî âèäíû. ß÷åéêà 00001000, íà êîòîðóþ ïåðâîíà÷àëüíî óêàçûâàë ðåãèñòð R5 î÷èñòèëàñü ( CLRB - CLeaR Byte - î÷èñòèòü áàéò ),çíà÷åíèå ðåãèñòðà R5 óìåíüøèëîñü íà 1 è òåïåðü óêàçûâàåò íà ÿ÷åéêó ïàìÿòè ðàñïîëîæåííóþ ïåðåä ÿ÷åéêîé 00001000, ò.å. 00000FFF.

2.5  ÊÎÑÂÅÍÍÛÉ ÐÅÆÈÌ Ñ ÀÂÒÎÓÂÅËÈ×ÅÍÈÅÌ

             ýòîì ðåæèìå ñîäåðæèìîå âûáðàííîãî ðåãèñòðà ÿâëÿåòñÿ àäðåñîì àäðåñà îïåðàíäà, à ïîñëå âûïîëíåíèÿ îïåðàöèè ïðîèçâîäèòñÿ óâåëè÷åíèå ñîäåðæèìîãî ýòîãî ðåãèñòðà íà 4, íåçàâèñèìî îò ðàçìåðà îïåðàíäà. Ýòî îïðåäåëÿåòñÿ òåì, ÷òî ðåãèñòð ñîäåðæèò àäðåñ àäðåñà ( ò.å. àäðåñ ÿ÷åéêè, ñîäåðæèìîå êîòîðîé â ñâîþ î÷åðåäü èñïîëüçóåòñÿ êàê àäðåñ äëÿ ïîëó÷åíèÿ äåéñòâèòåëüíîãî îïåðàíäà ), à àäðåñ âñåãäà ïðåäñòàâëÿåòñÿ êàê äâîéíîå ñëîâî.

            Äëÿ ïðèìåðà âîçüìåì îïåðàöèþ î÷èñòêè áàéòà, ìíåìîíèêà êîòîðîé íà àññåìáëåðå áóäåò âûãëÿäåòü êàê CLRB @(R5)+. Ñèìâîë '@' ( çþõà ) îçíà÷àåò èñïîëüçîâàíèå íå ïðîñòî ðåæèìà ñ àâòîóâåëè÷åíèåì, à èìåííî êîñâåííîãî. Ïðåäñòàâëåíèå ýòîé îïåðàöèè â ïàìÿòè áóäåò 94 95, ãäå 94 - êîä îïåðàöèè, 95 - îçíà÷àåò èñïîëüçîâàíèå ðåãèñòðà R5 è êîñâåííîé àäðåñàöèè ñ àâòîóâåëè÷åíèåì (öèôðà 9).

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