Quote Originally Posted by DaveC3 View Post
Without the LCD data sheet I don't think I can help ay more. Looking at the controller data sheet does not tell the whole story. There are different interfaces and component combinations for different VDD voltages and LCD manufactures. Where did you buy this LCD?

Dave
You are right Dave !

All LCD's was a gift for me from a friend. He gave me a printed paper with sumary of LCD(7pins):
- Display Type : TM202SIFSUGWA
- LCD OPERATING VOLTAGE : 4.8V
- VDD : 5V
- DRIVE METHOD : 1/16 DUTY ; 1/5 BIAS
- CONTROLLER : ST7036i
- pinouts, tolerance, etc

Really on boards I found 3 LCDs with different serials, but the boards are same, with the same functions. Actually I work on TM202SGFSGWA-B-1A . On internet I dont find a datasheet for them. I suppose that all LCDs with ST7036 controllers have the same init. The serials depending from manufacturers.

The LCD's are mounted on a working factory boards. I desolder the LCD from motherboard for test...also I make a test on a LCD directly on board ( of course that I cuted the tracks from sda, scl and reset pins for separate of rest components board) because I want to be sure that LCD was not destroied from desoldering. Any code I wrote in pic, I tested with potentiometer divider , with V0 short with Vdd.

I see in datasheet that contrast can be configured from registry(case V0 short with Vdd) or from external resistors divider.

Also I have LCDs with 8 pins but I have not any information about them....I have a information only from a serial printed on back LCD side(TM202TCCWUGWA)...here I suppose that have a 7032 controller, but is no important at this time.

Again thx for your help !