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OSVVM / AXI4

AXI4 Full, Lite, and AxiStream verification components. AXI4 Interface Master, Responder, and Memory verification components. AxiStream transmitter and receiver verification components
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First and Last Values when TKeep = 0 #10

Closed JimLewis closed 2 years ago

JimLewis commented 2 years ago

AxiStream Receiver currently provides '-' on last word if the Last bytes have TKeep = 0. Likewise for the first word if the first bytes have TKeep = 0. For all other bytes in a transfer if TKeep = 0, the byte is U or if TKeep = 1 and TStrb=0, the byte is W.

With '-' if TKeep is incorrect on the first/last word, then the test will pass anyway. This is bad, so '-' needs to be replaced.

Is U ok? I like U better than X as X can occur with multiple drivers (even though that should never happen). Or is 0 better? This would mean as long as the first and last bytes had non zero data it would be detected.

@Paebbels

JimLewis commented 2 years ago

Logging a Gitter conversation: RH thinks U would be better.

JimLewis commented 2 years ago

Updated to if TKeep = 0, the byte is U or if TKeep = 1 and TStrb=0, the byte is W.
Also added MetaMatch to allow for matching U and W in a string.