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<!--------------------------------------------------------------> <table width="100%"><tr><td align="left" valign="middle"><B>Re: Re: Re: Re: Tiskárna v CP/M:</B></td><td align=right valign="middle"></td></tr></table><BR><pre>Ještě jsem našel tohle: In the polled mode of printing, the character bits are put on the DATA lines, <img src="BODY_IMAGES_WRAP_GIF"> BUSY is tested repeatedly until it is found to be low, then the ~STROBE pulse <img src="BODY_IMAGES_WRAP_GIF">is sent. The printer sets BUSY high when the character data have been latched <img src="BODY_IMAGES_WRAP_GIF">and sets it low again when the character has been processed. (The Centronics <img src="BODY_IMAGES_WRAP_GIF">protocol specifies that the DATA lines be stable from at least 500 ns before to <img src="BODY_IMAGES_WRAP_GIF">at least 500 ns after the ~STROBE pulse, and the ~STROBE pulse be at least 500 <img src="BODY_IMAGES_WRAP_GIF">ns long. These times may of course be shortened for a specific printer, at the <img src="BODY_IMAGES_WRAP_GIF">risk of loss of generality.) Programs using the polled mode should include a <img src="BODY_IMAGES_WRAP_GIF">"timeout" counter to guard against a permanent BUSY condition. BIOS calls and <img src="BODY_IMAGES_WRAP_GIF">DOS functions use this mode for printing. Potvrzuje to moji domněnku s inicializací /STROBE a v podstatě i to zapsání <img src="BODY_IMAGES_WRAP_GIF">dat přímo do portu tiskárny (bez nutnosti úschovy v C). Kolik NOPů musím <img src="BODY_IMAGES_WRAP_GIF">dát na 500ns? To je jeden takt procesoru ne?</pre>