Lexicon PCM 90 - REV 1 User Manual page 24

PCM 90 User Guide
2-6
CRC: Indicates a Cyclic Redundancy Check error in the incoming data.
Parity, Biphase: Indicate that at least one bit (and therefore at least one audio
sample) was corrupted.
Parity, Biphase, and Confidence errors are most often caused by
inappropriate cabling. Be sure to use 75
kept as short as possible — standard audio cable will not work
reliably.
Each error is reported by name, with the number of occurrences of that particular
type of error. The display might show, for example "CRC: 4752". As many as
9999 instances of each error can be shown. If the number of actual errors
exceeds 9999, the display will indicate ">9999". A special symbol ( ) before the
error type indicates the most recently received error.
Press Load/ from the Dig In Status display and use ADJUST to scroll through the Error
Log.
A typical Error Log display showing that the last
error received was a CRC error ( CRC) and
that there have been more than (>) 9999 in-
stances of CRC errors since Word Clock was
last set to Ext.
To clear the Error Log, reselect Dig from the Control Mode Input Source
display. This will cause the PCM 90 to attempt to lock to the current external
source and will reset the Error Log. The log is also cleared on power up, and
whenever it relocks (Auto Lock On).
0.1 SCMS
Digital audio signals, in order to comply with copyright standards, are encoded
with control information which can limit the ability to copy audio data. This control
information is generally known as SCMS (Serial Copy Management System).
Under this system, you can choose to have the audio material processed by the
PCM 90 encoded to allow one of three levels of copy restriction. To make your
selection, use ADJUST to select No Copy, One Copy, or Multi Copy.
0.2 Emphasis Bit
The Emphasis control allows you to explicitly set the emphasis "flag" in the digital
audio, or to pass along the incoming signal without changing its emphasis
coding. (The PCM 90 does not perform any emphasis or de-emphasis as part
of its signal processing.) The choices available with ADJUST are: Yes, No, and
Pass Thru.
0.3 Output Level
This control allows you to select the maximum output level at the PCM 90's
analog outputs. Use ADJUST to select +4 dBu, or –10 dBu.
Exercise care when switching this control, as a 14dB level change
instantly occurs when going from -10dBu to +4dBu.
Lexicon
video-grade cable,
Audio Error Log
0.0 CRC >9999