Subject: re: crash with lpt driver
To: None <port-i386@NetBSD.ORG>
From: John M Vinopal <banshee@gabriella.resort.com>
List: port-i386
Date: 06/13/1996 16:29:17
the following patch fixes the problem.  comments?

>From jonas@carlstedt.se Wed Jun 12 07:13:44 1996
>----------------
>I have found a rather stupid (?) way to work around the problem,
>If i insert a DELAY(50) in lptintr (/sys/dev/isa/lpt.c around line 548):
>        if (sc->sc_count) {
>                u_char control = sc->sc_control;
>                /* send char */
>                bus_io_write_1(bc, ioh, lpt_data, *sc->sc_cp++);
>                DELAY(50);
>                bus_io_write_1(bc, ioh, lpt_control, control | LPC_STROBE);
>
>things seems to work allright. I'm not quite sure
>how long delay is needed, 10 doesn't work. I have also tested
>to move the DEALY call somewhat, and it doesn't seems to work if its later
>in the code.
>
>I don't have any bright ideas what to test more, and for the moment
>I can live with the DELAY loop since I still get a transfer rate of
>14 kbyte/sec when sending null-bytes to the printer
>(dd if=/dev/zero count=102400 count=1 > /dev/lpt0).
>-------------------