Re: Graphic LCD busy flag

From: Anton Erasmus (nobody_at_spam.prevent.net)
Date: 11/18/04 

Date: Thu, 18 Nov 2004 22:11:37 +0200

On 17 Nov 2004 04:14:36 -0800, leonlai2k@yahoo.com (terry) wrote:

>Hi,
>
>I am going to interface a KS0108 128x64 graphic LCD using AVR but
>encounter a big problem. I find that sometimes the program loops and
>hangs. I then stop the debugger and finds the program counter is
>looping to check the busy flag of the LCD.
>
>Anyone could help me or give me some hints to solve this?

Check your bus timing. Most of the LCD Display modules require,
VERY slow bus timing. Depending on which AVR you are using you
might be able to add wait states. If you are driving the Display via
normal I/O pins, then you still might have to add some NOPs to
slow down the bus cycle.

Regards
   Anton Erasmus