Altera 8B10B Encoder/Decoder MegaCore Function - Manual (Page 9)

Chapter 1: About This MegaCore Function 1–5
Installation and Licensing
May 2011 Altera Corporation 8B10B Encoder/Decoder MegaCore Function User Guide
OpenCore Plus Time-Out Behavior
OpenCore ® Plus hardware evaluation can support the following two modes of
operation:
■ Untethered—the design runs for a limited time
■ Tethered—requires a connection between your board and the host computer. If
tethered mode is supported by all megafunctions in a design, the device can
operate for a longer time or indefinitely
All megafunctions in a device time out simultaneously when the most restrictive
evaluation time is reached. If there is more than one megafunction in a design, a
specific megafunction’s time-out behavior may be masked by the time-out behavior of
the other megafunctions.
1 For MegaCore functions, the untethered timeout is 1 hour; the tethered timeout value
is indefinite.
Your design stops working after the hardware evaluation time expires, and the
following events occur:
■ For the encoder:
■ The ena input signal is forced low (deasserted).
■ The dataout output is forced to the k28.5 pattern.
■ The valid output is forced low (deasserted).
■ For the decoder:
■ The ena input signal is forced low (deasserted).
■ The dataout output is forced to all zeros.
■ The valid output is forced low (deasserted).