So I got the display working with the expected address(0x5C). It turned out to be the wiring that caused the problem. I feel kind of silly, but I am glad it is working. Thanks for your help I will let you know if I have any other questions.

Thanks Tom. Sorry the snippet doesn't show me loading DEVADD register with 5C, but I do. Here is the whole code. Like I said all I am trying to do is establish communication and display 'A'.

list P=PIC16C774
#include <p16C774.inc>
__config (_CP_OFF & _WDT_OFF & _BODEN_ON & _PWRTE_ON & _HS_OSC ...

I should get an acknowledge right? For both the address and the data going to the display. Right now, I am not getting one.

Thanks Miles.

Did you get my e-mail?

Here is my i2c code using MSSP. So I am moving the address of the display into DEVADD and the data I want to send into DATAOUT then call MyI2COut.


MyI2COut
;SLEW RATE CONTROL
movlw B'00000000'
banksel SSPSTAT
movwf SSPSTAT ;slew rate disabled

banksel SSPCON
movlw B'00111000' ;Enable I2C ...

HI,
I am developing an interface using the LCD2041 and a 4x4 matrix keypad. The microcontroller I am using is a PIC16C774 and I am programming it with assembly. However, thus far, I have been unable to communicate with the LCD. I can see the change on the SCL and SDA lines through an oscilloscope ...