Tektronix TDS5032, Manual

Page: 241 / 248

Measurement Algorithms
You can use the application to perform the following measurements:
High Speed Device:EL_21, EL_23, EL_25 (Sync-EOPIII-InterPacketII&III)
a. Complete procedures 1 and 3 to set up the oscilloscope.
b. The oscilloscope acquires and displays the waveform.
c. The application displays the message “Press OK when correct
waveform is acquired”.
d. The application measures the synchronous bits (32) of the third packet.
This is EL_21.
e. The application measures the EOP of the third packet (8bits). This is
EL_25. As the signal is differential, the EOP can be a positive or a
negative pulse.
f. The application measures the inter-packet gap between the second and
the third packets (88-192 bits). This is EL_23 as shown in the
following figure:
Figure 140: Measuring EL_23
TDSUSB2 Universal Serial Bus Measurement Package 227