Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Color TFT LCD - Init Code Cause Damage?

Status
Not open for further replies.

Noggin

Member
I'm working on trying to get a TFT LCD up and running on a PIC32. It has an ILI9325 controller on board and I was able to get it operating earlier today. I had it displaying full screen graphics and text. I used some init code I found in a PDF document for another display with the same controller. After I got this board working, I left it powered on and went to solder another LCD to another PCB to get it working too. When I came back to my desk, the first LCD had gone white screen and I have been unable to get it operating again.

Is it possible that using the incorrect init code damaged the LCD somehow? Like maybe the charge pumps went to too high of a voltage or something? Whenever I power on this board and the init code runs, the whole screen generally flashes to a solid color (though somewhat faded) usually green though occasionally blue or pink and then fades to white over about a time period of one second.

I'm waiting for the manufacturer to (hopefully) respond with some init code for this display. I have a document that describes all of the registers but I've given myself a headache trying to decode everything >,<
 
Last edited:
It is possible to damage some hardware with software. But I would THINK the LCD maker would make sure this could not happen. If possible it should be in the datasheet that you do not seem to have.

I would guess infant mortality if it is actually dead. As a rule I put my not working stuff aside and try it again much latter. This gives me a chance to "forget to make" the same mistake that I just made six or twelve times. :)
 
It is possible to damage some hardware with software. But I would THINK the LCD maker would make sure this could not happen. If possible it should be in the datasheet that you do not seem to have.

I would guess infant mortality if it is actually dead. As a rule I put my not working stuff aside and try it again much latter. This gives me a chance to "forget to make" the same mistake that I just made six or twelve times. :)

I hope you're right. Its just that it worked, and while it was working, it quit. The second board also worked the first time I programmed it, and after that it quit working. As I stated, I took an hour break and when I came back it worked well for a while even without reprogramming the MCU (edit: i guess I didn't say that in my original post). I know that there are charge pumps in these things as the gate voltages on the glass are in the 10v to 20v range and its powered from 3v. My hope is that the hour break gave ample time for the caps to discharge so that when I powered it back on it worked. However, this doesn't make a whole lot of sense and my gut is telling me that its wrong.

I have a 4 channel scope and I've scoped the CS, RS, and WR lines and they all look beautiful. I guess I'll just have to wait for the manufacturer to respond.
 
Last edited:
Well I got the proper init code from the manufacturer today, though it didn't change much. About one out of 10 times when I power on the board, I can see the text and chart image flickering faintly in the background for a second or two. Its almost like the display is refreshed and then quickly fades to white. I have disconnected the RGB interface on LCDs before and seen the display fade to white or black (I think it usually goes to white). It is similar to this.

Hmm.... I wonder what would happen if I had the micro continually redraw the entire image on the screen. As it is now, it draws it once and then goes away until an update is requested.

Edit: Result is full screen flickering. God I hope I didn't kill this LCD.
 
Last edited:
Formike Electronic KWH024Q04-F01 2.4" TFT LCD
 

Attachments

  • KWH024Q04-F01-TP ILI9325.pdf
    450.1 KB · Views: 643
HALLELUJAH!

The LCD wasn't damaged. I hand soldered the LCD to a PCB by way of a somewhat fine pitch 37pin flat flex cable. After working for several hours, one of the ground connections on the flat flex apparently failed. Spent 45 minutes resoldering it and its working again.
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top