Andre Abelian wrote:
>
> 1. are control instructions compatible to every lcd modules ?
Most LCD modules use the same Haitashi (sp) chip: HD4780. Have a look on
the back of your LCD.
> 2. is there any instruction for lcd to identify what kind of chip it uses ?
>
Not that I know of.

Looking at your code, I think your problem is in your initialising of
the LCD. It is especially critical for 4 bit mode:
Do it in this sequence (the binary is what must be send to LCD):

wait 15 msec
B'00110000' ;reset in 8 bit mode
wait 4 msec
B'00110000' ;reset in 8 bit mode
wait 1 msec
B'00110000' ;reset in 8 bit mode
wait 4 msec
B'00100000' ;Set LCD in 4 bit mode
set function ie: B'00101000' for 4 bits, 2 lines 5x7
display off
display on, set cursor
clear display
set increment

See the FAQ in piclist.com for more information. It's where I got my
answer from.

Quentin