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RE: LCD timing



In 2.4.19 you can enable FAST_TIMERS and use schedule_usleep.
You'll have to test if this works better than a polling solution
or not.

I assume that you don't write to the LCD very often? How much 
do you write each time? (1024 is a lot for a LCD, is it a large LCD?)
It may be ok to busy-wait for the LCD if you write small amounts
of data and not very often.


-----Original Message-----
From: owner-dev-etrax@xxxxxxx.com]On">mailto:owner-dev-etrax@xxxxxxx.com]On
Behalf Of Szabo, Tamas
Sent: Friday, November 22, 2002 8:25 AM
To: dev-etrax
Subject: LCD timing


Hello,

Currently I write a driver for LCD (ks0108 based). Unfortunately writing to
the display data RAM is very  slow (~10 us) and if I write 1024 bytes it
takes more than 10 ms. But as this routine in the kernel, most of this time
is just wasted. Since the display has no interrupt pin the checking of busy
is only possible with polling (continuously reading status register).

Has any suggestion to increase the efficiency?

Thanks in advance,
Sza2

Problems with Windows - Reboot.
Problems with Linux       - Be root.




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