just another1 with RGB-LCD Problems

[c-bob]

Hello fruities!

I'm new to *duino and everything related with embedded systems, but not new to programming.
My Problem: I've got an RGB LCD Shield Kit (#714) from watterott and assembled all parts. Now I want to try to use it by the provided example but nothing but the reset-button works.
If I maximize the contrast potentiometer I can see on the first line every dot is blacked out and the 2nd line is clean and there is no backlight.
Can I test the backlight without connection to my arduino mega 2560? BTW: which format are the *.brd and *sch files from gtihub? Tried gEDA and KiCAD (debian sid) but that doesnt work.

Thanks
-c-

[adafruit]

Are you using an R3 Mega? It is only plug-compatible with R3 Megas

[c-bob]

Hm, sorry, I dont know...I can not see anything on the board - only arduino mega 2560. How can I find it out?

PS: oops, sorry - on the arduino.cc page I've seen, that Imust have a Version before the R3... So what can I do?!

[c-bob]

Hm, I dont have eagle so I cannot open then schematics - darn!
And gEDA crashes by openeing the files
(BTW: I'm on linux)

[c-bob]

Oh, okay, I see - on Mega < R3 the i2c pins are 20 and 21 so I have to rewire only the 2 overlaping pins to the 20 and 21? Or must the pins A4 and A5 be cut?

[c-bob]

Okay guys, I got it. Rewireing is the Key - the upper left pins of the RGB-LCD-Shield has to be connected to pins 20 and 21 and then it works.

But another question: in example there was the following line:

Code: Select all

Serial.print("Took "); ... (no copy/paste possible)..bla.. (" ms");

Why does this appear on LCD? Isnt lcd.print!=serial.print?

[adafruit_support_bill]

Which example are you referring to?

[c-bob]

The hello-world-one on github : https://github.com/adafruit/Adafruit-RG ... ld-Library

[adafruit_support_bill]

And the "Took nnn ms" is showing up on the LCD?

[c-bob]

Jep, thats it! - maybe another pin-out problem on the mega2560? You know: the communication pins (0 and 1 of the first UART) are the first 2 pins connected to the shield?!

EDIT: But okay, I see: the UAT -Pins are not connected...

[adafruit_support_bill]

I'll see if I can track down an older Mega and give it a try.