User`s manual

118 • Troubleshooting Genie Color Series-GigE Vision Camera
Following are various examples of this data transmission problem. The solutions vary but commonly involve
reducing the maximum packet size claimed by the NIC used.
Grab has Random Bad Data or Noise – Case 1
• This problem has been seen on some computers where the NIC used does not fully support passing the
maximum jumbo frame possible from the Genie.
• In the NIC configuration, keep the jumbo frame size set to the maximum allowed. See "
Increasing Adapter
Buffers and Jumbo Frames" on page 24.
• Using CamExpert, test for a good acquisition by reducing the Genie packet size used. See "
CamExpert GigE
Vision Parameters" on page 64. Also check for packet resend messages with the Sapera tool "Log Viewer".
Grab has Random Bad Data or Noise – Case 2
• This problem has been seen with network adapters using the Realtek RTL8169 chip and associated low-level
driver. In this case the NIC reports a false maximum jumbo frame size.
• In the NIC configuration, set the jumbo frame size set to less than the maximum allowed. In this example the
NIC reports supporting a maximum jumbo frame size of 8384 but good acquisitions are possible only when the
size is reduced to 7k. See "
Increasing Adapter Buffers and Jumbo Frames" on page 24 and the image below.
• Using CamExpert, test for a good acquisition by reducing the Genie packet size used. Set the value to the new
reduced size set in the NIC configuration. See "
CamExpert GigE Vision Parameters" on page 64.
• Verify there are no packet resend messages with the Sapera tool "Log Viewer".
Grab has Random Bad Data or Noise – Case 3
• This problem has also been seen with network adapters that do not support jumbo frames but still report a false
maximum packet frame size.
• When using CamExpert, if the Network Configuration Mode is left as Automatic (default), CamExpert uses the
value the NIC reports as its maximum. This maximum value is actually not supported.
• Test for a good acquisition by reducing the Genie packet size used. Set the value to a starting value of 1500 to
verify acquisition before trying a higher value. See "
CamExpert GigE Vision Parameters" on page 64.