Matrix Orbital Corp

I have a LK204-25 with a keypad connected to the keypad connector. I am using a PICmicro MCU to communicate with the LK204-24 via RS-232. I have "Auto Transmit Keypresses Off" as I am using the "poll keypad command" to retrieve the buffered keypresses.

The problem I am having is that with the LK204-25's backlight on, the PICmicro MCU intermittently does not receive the buffered keys when polled. With the LK204-25's backlight turned off, all works great.

Anybody know why?

Thanks in advance.

David

post the order of bytes sent to the LCD when you see the problem and we'll try to duplicate it here.

I am providing the LK204-25 with an initial string of:

254, 88, 254, 69, 254, 80, 210, 254, 79, 254, 75, 254, 84, 254, 70

Then during a loop I continuously poll the keypad buffer about once per second with:

254, 38

All works great!

But if I turn the backlight on (254, 66), the PICmicro MCU intermittently does not receive the buffered keys. Turn the backlight off (254, 70), all works great again!

David