4) Setting Interrupt Moderation a. This value is often directly in the Advance Parameter list. Other times, this value is under Performance Options. It is typically set to adaptive. You can leave it at adaptive, or set it to extreme, or minimal when tuning system performance. 4.3 - Setting up Visionscape Registry for GigE Vision The section above described how to set up the NIC cards for each camera and to maximize NIC performance. The section below describes how to set up AutoVISION/Visionscape through the Registry to match the NIC settings and to maximize performance. Once done, AutoVISION/Visionscape will automatically program the cameras so they function correctly with these settings.
1) Setting Registry to Match NIC Card Setup The NIC cards have been set with IP Address, Subnet Mask, Packet Size, Receive Buffers and Interrupt Moderation. Next, each camera must be set to use the correct Packet size, Interpacket Delay, as well as Line Debounce Time for the Trigger Input. This is done through the Registry. a. Open the Registry by typing “regedit” in the start menu b. Navigate to the following registry key Using Sentech STC-M Cameras with AutoVISION and Visionscape Page 11 of 35 When a packet arrives, the adapter generates an interrupt that allows the driver (CPU) to handle the packet.
At greater link speeds, more interrupts are created and CPU usage increases which can result in poorer system performance. When you enable Interrupt Moderation, the interrupt rate is lower resulting in better CPU performance. However, this lower CPU usage can also result in dropped packets. Interrupt Moderation is generally set to Adaptive by default to allow interrupt rates to be set dynamically depending on traffic type and network usage. If your system is experiencing dropped packets, this value should either be set to Minimal to allow the CPU to handle the packets, or to Extreme to minimize CPU usage.
The user will have to experiment with this value because it is PC architecture dependent.