Waveshare 1.54" E-paper Display Issue

Other Hardware Displays
1

Hi,

I am trying to interface Waveshare 1.54" E-paper Display with PSOC-4 controller.

I have used Demo code given by Waveshare and have ported it for my controller.

At this initial stage i am just trying to clear the display screen but i am unable to do it though i am following the same Command and Data sequence given in demo code.

One more thing is that BUSY pin is staying always High(Busy) once display frame update command executed. I am not getting idea that why this is happening.

Can anyone help me in this issue??

Thank you.

2

What SPI speed are you using?

4MHz is safe, 8MHz should also work, see controller or display spec.

BUSY stuck high might be a consequence of some other issue.

I do not know PSOC-4, is it 3.3V ?

3

Thank you for your reply.

I did it and now my PSOC board is communicating with Display.

I have tried different image files and it is displaying all of them perfectly.

But another problem i got is that, I am unable to display String using library function listed in Paint.c.

Program stuck at below given function..its not exiting even single time.

void Paint_DrawAbsolutePixel(Paint* paint, int x, int y, int colored) {
if (x < 0 || x >= paint->width || y < 0 || y >= paint->height) {
return;
}
if (IF_INVERT_COLOR) {
if (colored) {
paint->image[(x + y * paint->width) / 8] |= 0x80 >> (x %8 );
} else {
paint->image[(x + y * paint->width) / 8] &= ~(0x80 >> (x % 8 ));
}
} else {
if (colored) {
paint->image[(x + y * paint->width) / 8] &= ~(0x80 >> (x % 8 ));
} else {
paint->image[(x + y * paint->width) / 8] |= 0x80 >> (x % 8 );
}
}
}

Not getting any idea that what exactly problem is.

Thank you.

4

Hi,

normally I do not analyze issues with the Waveshare library.

But I may, or someone else might analyze such an issue, if you provide all that is needed to compile and run an example that shows the issue.

The Waveshare code is made for AVR Arduinos, although the 5V Arduinos should not directly be connected to these 3.3V e-paper displays. The library assumes texts in PROGMEM, afaik.