There are some other pins on module (VCI for contrast, A1, K1 backlight LED, etc ...) but
the are unneccesary for this check.
Further, I know the LiquidCrystal Sketch is not for this 12x4 LCD (it shows somehow readable and mysterious characters), but it is possible to drive this LCD correct with amended settings in the sketch?
I have done some other projects with arduino uno but none with LCD...
Further, I know the LiquidCrystal Sketch is not for this 12x4 LCD (it shows somehow readable and mysterious characters), but it is possible to drive this LCD correct with amended settings in the sketch?
I have done some other projects with arduino uno but none with LCD...
According to the datasheet for the HD66712 it is 'upwardly compatible' with the HD44780 for which the LiquidCrystal library was written. As a result the instruction set is quite similar.
It certainly should be possible to control the device with your UNO although I am not sure if modifying the existing library would be easier than writing a new one. I wouldn't attempt to do either without having the hardware on hand.
If you have some programming experience (any processor) and you want to try then follow the LCD Programming Examples link at http://web.alfredstate.edu/weimandn for some ideas.
It would be interesting to know what the 'somehow readable and mysterious characters' actually were and that information might give some hints on how to proceed.
EDIT: You probably should go back and delete your other thread on this topic.
I have also salvaged the display from this old phone and have been partially successfull to make it work with he Uno and the LiquidCrystal library.
My problem is that the characters are being displayed "one row of pixels ahead", instead of centered on each segment. I'm not knowledge enough to find a solution by reading the datasheet or playing with the LiquidCrystal.cpp file, hence I'm here looking for some guidance.
A photo and the pinout of the LCD can be found here under Sagem RC712:
floresta:
According to the datasheet for the HD66712 it is 'upwardly compatible' with the HD44780 for which the LiquidCrystal library was written. As a result the instruction set is quite similar.
IMO, that was dumb design decision on their part.
I think that they should have done it the other way around. hd66712 should have been hd44780 compatible with extensions. That way it would work with existing code and existing 5x8 glass displays.
It certainly should be possible to control the device with your UNO although I am not sure if modifying the existing library would be easier than writing a new one. I wouldn't attempt to do either without having the hardware on hand.
If I understand the datasheet correctly, and the only issue is the font width, I think you can get away with a few tweaks to the sketch and use the existing hd44780 library code with no modifications.
i.e.
After your lcd.begin(12,4) call.
Just add:
lcd.command(0x2c); // Function set: 4 bit mode, 2 line mode, enable RE bit
lcd.command(0x0d); // display control: 5x8 font mode, enable 4 line mode (ignores 2 line mode)
lcd.command(0x28); // Function set: 4 bit mode, disable RE bit
Unfortunately that did not have any effect. Also, the display started having the same erratic behavior the OP mentions in the first post, with random characters being displayed more or else randomly after uploading. Ex: 123456789 would show as "#$#/@[]{€ or similar.
I am reading this book in order to try to understand how the HD44780 is programmed according to the info in the datasheet.
I find it difficult to get stuff like this correct without having the actual part in hand as sometimes the datasheets are not very clear and in some cases are even incorrect, so unfortunately, I can't really help any further since I don't have one of these types of displays.
