normal environment should be virtually free of bus parity errors
Bus parity errors cause the drive to either retry the operation, go to STATUS phase, or
Retrying of parity errors during Data Out Phase when writing is normally not done,
but can be enabled by changing the EnaParErrRetry parameter in the VU EEROM
device performance (the data stream on writes cannot be pipelined as well).
DLT4000/DLT4500/DLT4700 Cartridge Tape Subsystem -7