FoxyRick
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Hi all,
I have a box (144) of Winteck 16x2 LCD displays. The datasheet (which is minimal) says that the controller is a KS 0070. I have read conflicting reports of this; some say it is completely compatible with the HD 44780, some say the timing requirements are completely different.
Has anyone used an LCD with this controller? I am writing code in CCS PICC, with the built-in LCD routines which work with HD 44780, but I can't get any response from the LCD. The code checks for the 'busy' signal to drop before writing, and it never gets past that stage. Swapping for a HD 44780 LCD works fine, so the code and circuit is OK for that.
Also, I am unsure of the LCD drive voltage. The datasheet states 'Vdd-Vo = 4.5V typical' where Vdd is 5V supply. Does this mean the LCD drive (Vo) should be 0.5V? I have attached a 10K potentiometer to drive this pin, but cannot get anything on the display at any setting. Usually, an LCD will show a contrast change even if it is not getting data (just has power).
Either I am doing something wrong (needs different code, wrong LCD drive voltage) or my displays are dead.
FoxyRick.
I have a box (144) of Winteck 16x2 LCD displays. The datasheet (which is minimal) says that the controller is a KS 0070. I have read conflicting reports of this; some say it is completely compatible with the HD 44780, some say the timing requirements are completely different.
Has anyone used an LCD with this controller? I am writing code in CCS PICC, with the built-in LCD routines which work with HD 44780, but I can't get any response from the LCD. The code checks for the 'busy' signal to drop before writing, and it never gets past that stage. Swapping for a HD 44780 LCD works fine, so the code and circuit is OK for that.
Also, I am unsure of the LCD drive voltage. The datasheet states 'Vdd-Vo = 4.5V typical' where Vdd is 5V supply. Does this mean the LCD drive (Vo) should be 0.5V? I have attached a 10K potentiometer to drive this pin, but cannot get anything on the display at any setting. Usually, an LCD will show a contrast change even if it is not getting data (just has power).
Either I am doing something wrong (needs different code, wrong LCD drive voltage) or my displays are dead.
FoxyRick.
