Hi,
I've a problem with my TFT touch screen.
It uses the SSD1289 driver and is connected to the Arduino Mega 2560.
I uploaded different example but I've always the same problem.
The screen shows all data on top of old data.
Also when the system boots after a new upload and the screen goes on there is data from the old program and/or colored noise over the hole screen.
I've made a video from the problem link:
Can please someone help me and tell me what's going wrong.
Kind regards.
Hoi Dageraad, en welkom.
It seems to me that there is some problem with the initialization of the display.
I have no experience with these display yet, but i see you have soldered wires to it.
How long are these wires ?
And are you sure you did a good soldering job on every wire ?
To me it looks like you need to do a clear screen, fill the display memory with all zero's or one's, before you write new data to the display, otherwise you will write over the old data. The noise you see after bootup is your display-memory that has undefined states and that looks just like noise.
MAS3:
Hoi Dageraad, en welkom.It seems to me that there is some problem with the initialization of the display.
I have no experience with these display yet, but i see you have soldered wires to it.
How long are these wires ?
And are you sure you did a good soldering job on every wire ?
The wires are about 50 cm long. I've soldered the wires to it because I thought it could maby be a connection problem. I measured every wire after soldering and the connections seems to be okay.
cartoonist:
To me it looks like you need to do a clear screen, fill the display memory with all zero's or one's, before you write new data to the display, otherwise you will write over the old data. The noise you see after bootup is your display-memory that has undefined states and that looks just like noise.
I think this wouldn't solve the problem because I've tried differend examples with all the same problem. Fill the display with zero's will maybe solve de noise problem on startup but not problem that all the images of the demo (circles, waves etc) are stacked on top of each other.
Hi.
Filling the buffer with zeros or FF will effectively erase the old picture (by making each pixel either black or white).
But that's one of the things that are part of the initialization of the screen.
50 cm (1.6 feet) is a lot of wire.
Those might very well act as antennae.
That's 32 possibilities of catching signals which will be misinterpreted as valid data.
Most displays use a pin to know the data coming in is data to be displayed, or some command.
Such a command could be to erase the contents of the screen.
So perhaps it's a good idea to find out if your display does have such a pin, and if so recheck its connection.
And also check to see if that pin is working correctly, you might be coping with some defect.
Problem is solved.
I replaced and shortened the cable. Now its working fine.
Thanks for support so far.
Regards