Input Resolution Detected Incorrectly for Analog Source

Some computer and video resolutions can be mis-detected on CORIO2 units if the source is analog.

This is because the CORIO2 unit only has the horizontal and vertical frequencies (plus the sync polarities) to measure in order to work out the correct resolution for the incoming analog source. For digital sources, there is no problem - since there is a clock signal available that can be used to measure the number of active pixels per line.

With just H & V frequencies, almost all resolutions can be detected properly - except those that share the same H & V frequencies but have different numbers of pixels per line.

An example of this is XGA (1024x768) and WXGA (1360x768). Although most sources will change the H & V sync polarities to allow proper detection, some do not. Both of these resolutions use similar H & V frequencies and so the CORIO2 unit, depending on the actual frequency of the source, may pick the wrong one.

If this occurs, it is best to remove the 'bad' resolution from the CORIO2 unit's database. A simple way of doing this is to toggle the Interlaced setting. To do this, go into 'Adjust resolutions' for the resolution you want to remove, and swap over the Interlaced setting from Off to On (or vice versa). Dis-connect and re-connect your source, and the 'bad' resolution will no longer be detected.

Take care not to remove resolutions you want to use. If you lose track of which resolutions you've removed in this way, or need to put things back to factory settings, you will need to perform a firmware update.