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kzeoprf
- 1st September 2011, 08:39
Hi I am new in this forum, and I want to ask a question concerning the swapping of the two lcds. It seems in this forum there is great experiance in LCDs. Is it possible without changing nothing (swap lcd 16x2 with 20x2)? I have a situation where the 16x2 (lcd1602 blue backlight) is working ok but when I use the 20x2(rt2002a2 blu backlight) it does not. If I connect all the pins on the 20x2 I get in the the straight line but in very week black color. No messages -data. If I disconect RW or/and EN then I get the straight line white OK but no messages. I use starnded hook up wire to connect the LCD with the PIC. Do you have any clue what to do. The fact is that I have a delevirable and last moment I have to use biger display and it does not work.
Any help is welcome. Is there any chance the LCD to be out of order? I am waiting for a new one.

Ioannis
- 1st September 2011, 09:02
1. Maybe the new LCD is slower so it needs more start up time. Look for the LCD_COMMAND and LCD_DATAUS DEFINE's.

2. What about the contrast setting ofthe LCD?

Ioannis

kzeoprf
- 1st September 2011, 09:25
Thanks for the reply. I tried this is the same. The strange think is that when I connect the enable or RW the line goes weak black from white.

Archangel
- 2nd September 2011, 01:24
Hi I am new in this forum, and I want to ask a question concerning the swapping of the two lcds. It seems in this forum there is great experiance in LCDs. Is it possible without changing nothing (swap lcd 16x2 with 20x2)? I have a situation where the 16x2 (lcd1602 blue backlight) is working ok but when I use the 20x2(rt2002a2 blu backlight) it does not. If I connect all the pins on the 20x2 I get in the the straight line but in very week black color. No messages -data. If I disconect RW or/and EN then I get the straight line white OK but no messages. I use starnded hook up wire to connect the LCD with the PIC. Do you have any clue what to do. The fact is that I have a delevirable and last moment I have to use biger display and it does not work.
Any help is welcome. Is there any chance the LCD to be out of order? I am waiting for a new one.I would check the pin out on the LCD maybe one of them is non standard, also make sure to bypass the power input pins with a smal cap. Some are a bit sensitive to noise, I found.

kzeoprf
- 2nd September 2011, 16:25
I done that but the same think. The 20x 2 lcd was chosen due to they have the same controler and the same initialization sequense. I think do not have any options to wait the new lcd.