System information

32
To Acquire a Serial Bit
Stream without an External
Clock Reference . . .
...set the sample period
of your timing analyzer
to take four or more
samples for each
serial bit.
...accept the
“Samples” default
label or enter a new
label name.
...specify the embedded
bit time of the serial bit
stream.
...specify the incoming
signal’s data encoding
method, normal or
NRZI.
Clock Recovery Algorithm
1. For analysis purposes the data is
captured in conventional timing
mode using the internal timing
analyzer clock as the clock
reference. Set the sample peri-
od of the timing analyzer to take
four or more samples for each
serial bit.
How Clock Recovery Works
Embedded bit time
Incoming serial bit stream
Timing analyzer samples
(with timing analyzer set
to take five samples for
each serial bit)
New “Samples”serial data
0000000000000000000001111111111111111111111111111
00001111 1
2. The timing analyzer data is sam-
pled in the middle of each bit
according to the serial bit rate
defined in the clock recovery
window.
3. Data edges (transitions from 0
to 1 or 1 to 0 in the timing
analyzer trace) are used to
resynchronize the sampling.
Resynchronize on edge
The Serial Analysis
Tool Set (continued)