Hi,
I must retire. I checked and it seems really so, that PRINT itself does
not use the IRQ of the printer. The following statement has deceived me:
"IRQ 7 [ ... means] data request on LPT1" from Helppc. It seemed logical
for me...
Sorry again.
Imre

>
> On Tue, 18 May 1999, Peter van Hoof wrote:
>
> > The dos print spooler polls the parallel port on the timer interrupt, no
> > interrupt from the printer is needed
> >
> > -timer interrupt jumps to hooked service routine (about 18 times a second)
> > -printer status check
> > -if printer buffer empty send new characters
> > -if printing done unhook timer interrupt
> > -jump to original timer service routine
> > -original timer service routine returns controll to dos till next timer
> > interrupt
> >
> > Peter pvh@vertonet.com
> >
> >
> > -----Original Message-----
> > From: Sean Breheny <shb7@CORNELL.EDU>
> > To: PICLIST@MITVMA.MIT.EDU <PICLIST@MITVMA.MIT.EDU>
> > Date: Tuesday, May 18, 1999 8:42 PM
> > Subject: Re: Multitasking without interrupt ?
> >
> >
> > >Hi Imre,
> > >
> > >How does it work on PC's without a printer IRQ? I thought I had used it on
> > >ones that probably didn't have a printer interrupt.
> > >
> > >Sean
> > >
> > >At 11:32 AM 5/17/99 +0200, you wrote:
> > >>Hi,
> > >>only as a small remark: the DOS print spooler (I do not know whether
> > >>another ones...) is working on an interrupt basis, as the printer tells
> > >>with an IT if the data has been printed, so asks for new data. There is no
> > >>time slicing.
> > >>Imre
> > >>
> > >>
> > >
> > >|
> > >| Sean Breheny
> > >| Amateur Radio Callsign: KA3YXM
> > >| Electrical Engineering Student
> > >\--------------=----------------
> > >Save lives, please look at http://www.all.org
> > >Personal page: http://www.people.cornell.edu/pages/shb7
> > >mailto:shb7@cornell.edu ICQ #: 3329174
> >
> >
>
>