NIOS II pixel buffers shows strange dots on VGA screen

[AAlas3]

Hey,

I am using DE2-115, my problem is when I use Pixel buffer to draw anything on the screen it works but it also draws small strange dots with different colors, I tried to clear the buffers but they still appear.

Thanks in advance

[Ahmed_H_Intel1]

Hi,

Did you assign a default slave IP to clear all the invalid transactions?

Are you using a DMA to stream on this screen?

Regards

[AAlas3]

Yes clearly the pixel buffer is with DMA, what do you mean by slave IP ?

[Ahmed_H_Intel1]

The slave IP is an option to assign an IP as a slave IP in Qsys. This helps to clear any invalid transactions that might cause a glitch in the system.

You can simply add a PIO IP into your Qsys design and then assign this IP as a default slave as shown in the image below.

[Ahmed_H_Intel1]

Assigning a default slave