Average Data RateThe average data rate is the speed at which the software receives an entire frame from the camera, and is determined programmatically by the frame rate. If a frame is too large to transfer all of the data across the bus in the allotted acquisition time, we will experience an acquisition timeout error.
I am acquiring a 1280x1024 12-bit image at 10 frames per second using a PCIe-1427 frame grabber. My camera has a clock rate of 80 MHz and the board is in a 1x PCIe slot. I am using a 2-tap configuration. Can I successfully perform a snap acquisition?Note: The PCIe-1427 has 16 KB of on-board memory. A 1x PCIe slot has a maximum throughput of 200 MB/s.
80M pulses/s x 2 pixels/pulse x 2 Bytes/pixel = 320 MB/sSince 320 MB/s > 200 MBs then we will begin filling the on-board FIFO.
320 MB/s – 200 MB/s = 120 MB/s
(1280 pixels/line x 1024lines/frame) / (2 pixels/pulse x 80 pulses/s) = 8.2e-3 s/frame
120 MB/s x 8.2e-3 s/frame = 984 KB/frame
Since the FIFO required for one frame is greater than the on-board memory (984 KB > 16 KB) we will experience a buffer overflow error during this acquisition.
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