The FPD-Link III Receiver may be programmed to require a specified number of valid video frames prior to indicating a Pass condition and forwarding video frames. The number of required valid video frames is programmable through the PASS_THRESH field in the PORT_PASS_CTL register. The threshold can be programmed from 0 to 3 video frames. If set to 0, Pass will typically be indicated as soon as the FPD-Link III Receiver reports Lock to the incoming signal. If set greater than 0, the Receiver will require that number of valid frames before indicating Pass. Determination of valid frames will be dependent on the control bits in the PORT_PASS_CTL register. In the case of a Parity Error, when PASS_PARITY_ERR is set to 1 forwarding will be enabled one frame early. To ensure at least one good frame occurs following a parity error the counter should be set to 2 or higher when PASS_PARITY_ERR = 1.