Matrix Orbital Corp

Can I use the LK204-25 REV1.23 with an Arduino. I've tried many different code scripts and none seem to work. I tried adding a pull-up resister to the data pins. I tried adjusting for the 7-bit addressing. Nothing seems to work. I only get two black lines on the LCD display.

I am guessing that the problem has to do with the RS-232/I2C protocol selection. Much of the documents that I've read state to move a jumper or SMD resister to convert it to I2C mode. There are several places on the bottom of the board where jumpers or SMD resisters can be added, but none of the locations are labeled.

Is it possible that I can use the Rev. 1.23 board with the Arduino? If so how?

Thank you for posting on the forum.

Getting two black lines (rows 1 and 3 especially) from the LCD display may indicate a damaged display.
If you were to power the display on its own, ie pin 1 and 4 of the power connector only to +5V and GND respectively, do you still see the lines?

Hi Seth,

To elaborate on your question about the soldering of resistors to place your Rev1.23 unit into I2C mode, please ensure you consult the correct manual. The Rev1.23 is actually an older unit that requires jumper changes only, no soldering at all.

Please try Raquel's suggestion and let us know what you see.

Thanks,
Troy

Raquel,
Yes, I have been getting the two black lines pretty much consistently. I was expecting to see some sort of startup screen, but I get the two lines as soon as I power it up. I know that the device has been fully functional in the past, but it must have gotten damaged at some time.

Troy,
The reason that I posted here is because I have been unable to find the exact manual for the ver 1.23. I have been bouncing back and forth between the ver 1.2 manual and ver 2.0 manual looking for bits and pieces here and there that would help.

Oh, well, it's a moot point now. It seems like it is broken. I love your products. I'll go and see what's currently available for sale.

Hi Seth,

I'm sorry to hear that old unit appears to have passed away, I think you'll find we've added a number of new features to our products in the years since the release of the LK204-25 Rev1.23. If you plan to continue development with your Arduino, you might find this appnote helpful.

Thanks,
Troy