UPGRADE YOUR BROWSER

We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome, Firefox, Internet Explorer 11, Safari. Thank you!

Reply

VDMA 6.2 does not write all pixel into memory

Highlighted
Newbie
Posts: 2
Registered: ‎10-12-2017

VDMA 6.2 does not write all pixel into memory

Hi,

we are using the Axi VDMA 6.2 IP Block to receive 12bit data from a monochrome camera.

We are using the write channel with a memory map datawidth of 32, a burst size of 8, a data stream width of 16 and a line buffer depth of 512.

The VDMA is configured correctly and does not produce errors.

 

We however encounter a strange problem:

At random intervals, sets of 16 pixels (32byte) are not written into memory. The VDMA seems to just skip these pixels and continue on. The image is not misaligned, just random sets of 16 pixel are missing.

We also verified with ILA, that our video signal is correct.

 

We would be very thankful, if someone could give us a clue on how to solve this problem.

Scholar
Posts: 2,187
Registered: ‎04-26-2015

Re: VDMA 6.2 does not write all pixel into memory

When you say "missing" - are they written to zero, or are they just not written?

 

What hardware is this running on, and at what frequencies? The obvious potential issue I can see is that somewhere there's a block that can't keep up with the camera (eg. a low-speed AXI Interconnect) and so it's just dropping a whole transaction.

Newbie
Posts: 2
Registered: ‎10-12-2017

Re: VDMA 6.2 does not write all pixel into memory

The values are not written at all.