AVR-Chat

Owen A wrote:
> I have a few 4X40 LCD's that display rubbish without adding a 220nf cap to gnd on the lcd bios pin.
>   Owen.
> 
> John Samperi <samperi@ampertronics.com.au> wrote:
>           At 02:01 AM 23/08/2007, you wrote:
> 
>> Kathy Quinlan wrote:
>>> I have had problems with Ampire displays and static, I found that by
>>> grounding the LCD Bezzle I could stop this problem.
>> Have had a quick go at this but no change - did you get the same
>> symptoms or did the static problem perhaps stop it working completely?
> 
> I have temperature related failures of LCDs. On a hot day and after
> running for a while the LCD stops working correctly, the same code
> works well with other brands of LCDs, don't know what chip it uses,
> just 2 blobs.
> 
> I have heard of people putting small caps (15pf or so) in the E line,
> don't know if this will help with your problem or mine.

The 44780 internal clock may be slowing with temperature, and silicon
gets a bit slower with heat too iirc. I'd put more time delays between
every operation to narrow down where the timing problem is.