What is Overstep?

OVS (OVerStep) is a phenomenon where the DMA engine cannot keep up with the data stream from the camera. The most common reasons for this are:

  • The BW of the camera video stream is higher than the BW of the PCI interface
  • The MB bridge(s) will not give enough access to the PCI for frame grabber DMA engine

Obviously, high activity on the MB will generate OVS. We always suggest to customer to stop activity while acquiring data from the camera. Access to disc or high intensity graphics are the usual suspects.