[Linux-parport] Parport signals stability with SiS chipset
tdlt at cecm.usp.br
tdlt at cecm.usp.br
Tue Mar 2 09:44:24 GMT 2004
I have the same problem here. My two computers have SiS chipsets
and the signals at pins are not set up correctly (at least not
as I would like to see them).
When I write data to ports using outb(), the pins change for a
while and return to the initial state. In the initial state some
pins are high and others are low. Using a latch and one control
pin I could notice that the pulse is maintained by at least 1us.
The voltage at control pins are stable. I could set it once and
measure the desired voltage after a long time (not one year but
lots os seconds).
I should use my circuit and I programmed it in MS-DOS
where this problem doesn't exist while using the same computers.
--
Thiago A. M. Delatorre
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