R&S RTO6, Руководство пользователя

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Protocol analysis
R&S
®
RTO6
726 User Manual 1801.6687.02 ─ 05
7. To start searching the acquired waveform for specific events, tap "Enable" in the
search setup dialog:
The R&S RTO6 displays the "Search Results" box that lists the detected events.
For information on how to configure the search results presentation and how to navi-
gate the search results, see also
"To display search zoom windows" on page 442.
13.15 Ethernet 10BASE-T and 100BASE-TX (option
R&S
RTO6-K540)
Twisted-pair Ethernet technologies are based on the family of standards IEEE 802.3,
issued by the Institute of Electrical and Electronics Engineers (IEEE).
R&S RTO6-K540 is a firmware option that enables the R&S RTO6 to analyze Ethernet
protocol variants 10BASE-T and 100BASE-TX, by decoding the signal and searching
within the decoded events. It is possible to trigger on 10BASE-T signals and 100BASE-
TX signals. The option is compatible with the standards IEEE
802.3i of 1990 (10BASE-
T) and IEEE 802.3u of 1995 (100BASE-TX).
● The Ethernet protocol ............................................................................................726
● Ethernet configuration ...........................................................................................727
● Ethernet trigger ..................................................................................................... 732
● Ethernet decode results ........................................................................................ 736
● Search on decoded Ethernet data ........................................................................ 737
13.15.1 The Ethernet protocol
The two Ethernet protocol variants that R&S RTO6-K540 can process have the follow-
ing features:
●
10BASE-T uses Manchester coding (or phase encoding, PE). In terms of a logical
Boolean operation, the Manchester value of each bit is the exclusive disjunction
(XOR) of the original data value and the clock value. A "0" is expressed by a high-
to-low transition, a "1" by a low-to-high transition. These transitions, which occur at
the middle of each bit period, make the signal self-clocked.
●
100BASE-TX uses a 4B5B multi-level transmit (MLT-3) encoding. The protocol
sequentially cycles through a sequence of the voltage levels -1
V, 0 V, +1 V, and
0 V. To transmit a "1" bit, MLT-3 moves to the next state; to transmit a "0" bit, it
stays in the same state. 4B5B block coding is used to map groups of four bits onto
groups of five bits. Also, the signal is scrambled.
All Ethernet-over-twisted-pair technologies use wires with four twisted pairs of cables
(and 8P8C connectors), but 10BASE-T and 100BASE-TX only require two pairs of
wires.
Ethernet 10BASE-T and 100BASE-TX (option R&S RTO6-K540)