Hi guys. After testing to making sure that things work, we finally came up with the code for C18 that successfully sends data to the LCD via I2C. The code is listed below:

#include "p18f252.h"
#include "i2c.h"
#include <stdlib.h>

#pragma config WDT = OFF
#pragma config OSC = HS

unsigned char ...

Hi Raquel. My friend changed the codes a bit, and right now the LCD is responding with ACKs and we are sending data over. However, they are not displayed on the LCD.

Also, instead of 0x50, my friend used 0xA0, which is 0x50 shifted by one bit and the LCD ACKs. He also ued idleI2C() to produce the ...

Hi Raquel. Here's the pictures of the PCB board behind the LCD. Hope you can find the problem soon.





Thanks.

Yu-Chen Shih

Hi Raquel. Nope, we did not change the slave before, and the reset pins are both jumped during the testing and scope capturing. The slave address we're using is 0x50.

Thanks.

Yu-Chen Shih

Hi. I just got the scope captures and here they are now. For these scope captures, we used putcI2C() instead of putsI2C(). PutcI2C sends one char at a time, while putsI2C sends a whole string at a time. However, putsI2C doesn't have line idle high at the end but putcI2C does. Below is the new scope ...

Hi. I see, I guess there's no way to bypass it then.

As for the pin lifting, we already did that and followed the instructions there but still didn't get anything.

My friend will be getting more scope captures later today according to your suggestion about capturing signals on the display side ...

Hi Raquel. We got everything setup the way you said so, but we're still not getting any ACK from the LCD. I was wondering if we use writeI2C() (i2c_writ.c) and ackI2C() (i2c_ack.c) and send one char at a time would it bypass having to check for ACK from the LCD and just sends data to it instead ...

Hi.

I see, we'll try MOGD and see if it fixes the baud rate issue. Although asides from that MOGD works fine in terms of bitamp uploading and text input testing.

The scope capture is listed below. I hope it will be of help in solving the problem.

http://img.photobucket.com/albums/v43/techys ...

Hi. We have Rev 1.4. I checked manual 1.4 and 2.0, but 254/160/0 command is not listed in either manual's command list. It is only mentioned by manual 2.0 in the I2C section on page 16.

Yu-Chen Shih

Hi again.

I found something on the manual today that could be the problem. Under the I2C section, it says to input the following commands 254/160/0 to the LCD to turn off the auto transmission of data in RS232. I checked the commands list and didn't see this anywhere, and we can't apply this ...

Hi Raquel.

I will get you the scope captures tomorrow (because I'm not the one doing it, and the equipments are not at my place either), but I can explain some weird things about them right now. For one of the lines (I think it was SDA line) the voltage seems to drop below 5V while the other one ...

Hi. My name is Yu-Chen. Some friends and I were trying to get the PIC18F252 to transmit data to the GLK12232-25-SM LCD via I2C. However, we are running into some trouble about the LCD not accepting input data.

The LCD is setup according to the changes indicated for PCB 1.4 of GLK12232-25-SM for the ...