Assembler äëÿ íà÷èíàþùèõ
Àäàïòåð ïàðàëëåëüíîãî ïðèíòåðà - ÷àñòü 2
ïðîâåðÿåò ñîñòîÿíèå, ÷òîáû âûâîäèòü ñëåäóþùèé ñèìâîë èìåííî òîãäà,
êîãäà ïðèíòåð ãîòîâ åãî ïðèíÿòü. Áèò 7 ñîñòîÿíèÿ ïîðòà ââîäà
ïîêàçûâàåò çàíÿòîñòü ïðèíòåðà. Åñëè ýòîò áèò ñîäåðæèò 1, ïå÷àòàþùåå
óñòðîéñòâî ãîòîâî ïðèíèìàòü ñëåäóþùèé ñèìâîë äëÿ ïå÷àòè. Â
ïðîòèâíîì ñëó÷àå ïðîãðàììà äîëæíà ïîäîæäàòü. Îñòàëüíûå 4 ââîäíûõ
áèòà ýòîãî ïîðòà îòðàæàþò âîçìîæíûå îøèáêè íà ïå÷àòàþùåì
óñòðîéñòâå, íàïðèìåð, îòñóòñòâèå áóìàãè. Íàø ïðèìåð íå êîíòðîëèðóåò
ýòè ñèòóàöèè. Òåõíè÷åñêîå îïèñàíèå ñîäåðæèò ñòðóêòóðû ââîäíûõ è
âûâîäíûõ ïîðòîâ ïëàòû àäàïòåðà ïå÷àòàþùåãî óñòðîéñòâà.
Microsoft (R) Macro Assembler Version 5.00 1/1/80 04:05:39
Ôèã. 8.15 Âûâîä íà ïðèíòåð Page 1-1
PAGE ,132
TITLE Ôèã. 8.15 Âûâîä íà ïðèíòåð
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