1) What do you need an RGB back light for?
2) Where do you get one for a better price?
BTW, it seems sparkfun screwed up by ordering some common-cathode displays, not pin-compatible with regular LCDs on the part that pin 15 is A pin 16 is K (sparkfun's has pin 15 K and pin 16 A)
Ebay is disappointing. No hit for "character lcd rgb":http://www.ebay.com/sch/i.html?_from=R40&_trksid=p5197.m570.l1313&_nkw=character+lcd+rgb&_sacat=See-All-CategoriesIf you try "character lcd", there's too many hits to sift through.
I'm thinking of using this RGB display for my serial panel but that means I won't be able to reserve the I2C pins for future I2C interface since two more LEDs need two more pins.
What about the chinese wholesale sites like alibaba ? I looked but did not spend much time at it. They may have some.
@dc42, I have not thought about that. So do you mean maybe using the 4 LCD data pins to drive the columns of the matrix keypad? Should be doable without much modification of my original code, right? I don't sense the keypad and update LCD at the same time.
I haven't thought about using diodes. So are they there to isolate what happens on the LCD pins from the keypad or are they isolating what the keypad does from the LCD? I know that the LCD could write on the data pins but I don't think I need the LCD to do that. I have a display buffer on the arduino.
This any good?http://www.ebay.co.uk/itm/ART-New-LCD-2x16-F-LED-b-l-RGB-HD44780-H-30mm-ABC016002F00-MIRGB-R-/320795737775?pt=LH_DefaultDomain_212&hash=item4ab0ea7eaf#ht_754wt_952Price is very cheap!