Rohde & Schwarz RTP044 - 8 B;10 B (Option R&S RTP-K52); The 8 B;10 B Code

Protocol analysis
R&S
®
RTP
774User Manual 1337.9952.02 ─ 12
3. If the dialog box does not contain a search entry, tap the "Add" icon to create one,
as described in "To create a user-defined search" on page 463.
4. Specify search criteria according to Chapter 13.15.6.1, "Custom Manchester / NRZ
search setup", on page 772.
5. To acquire a waveform, press [Single].
The R&S RTP performs a custom serial bus decode according to the thresholds
and protocol settings of the associated serial bus source (here in our example
SB1).
6. To start searching the acquired waveform for specific events, tap "Enable" in the
search setup dialog:
The R&S RTP 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 470.
13.16 8b/10b (option R&S RTP-K52)
The 8b/10b coding scheme is used for high-speed serial data transmission, used by
different standards, like fibre channel, PCIe, DVI and USB 3.0. Also the MIPI UniPro
M-PHY interface in smartphones and display interfaces such as HDMI use 8b/10b
encoding, as do base stations based on the Common Public Radio Interface (CPRI).
The R&S RTP can decode differential and single-ended 8b/10b signals. Furthermore,
you can search the decoded data to isolate data contents and error states such as dis-
parity violations.
You can also trigger on defined data contents and on error states.
● The 8b/10b code................................................................................................... 774
● 8b/10b configuration..............................................................................................775
● 8b/10b trigger........................................................................................................780
● 8b/10b decode results...........................................................................................783
● Search on decoded 8b/10b data...........................................................................784
13.16.1 The 8b/10b code
The 8b10b is a code where an 8-bit parallel data input is mapped into a 10-bit output.
This code achieves a DC-balance and bounded disparity and simultaneously allows a
reasonable clock recovery.
In the coding scheme, the original 8 bits are split into two blocks, three most significant
bits and five least significant bits, see Figure 13-19. After that the 3-bit block is enco-
ded into 4 bits and the 5-bit block into 6 bits. The 4-bit and the 6-bit blocks are then
combined into a 10-bit.
8b/10b (option R&S
RTP-K52)