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Data Cards 17-7
OCU-DP Card OCU-DP Card User Screens and Settings
ERR COR
The Error Correction setting is used only on the OCU-DP 2 Card. It provides different
methods of error correction, depending on the data Rate selected. The default ERR COR
setting is off. If you choose subrate speeds of 9.6k or less in the Rate setting, the Error
Correction option maj-v (majority voting) is available. Using majority-vote error correction
allows the system to poll the data for errors and decide on the correct data based on the
repeated bit pattern.
The bch error correction option is available for 19.2K only. Bch Error Correction is not
supported on the OCU-DP5 or OCU-DP 10 Card. Maj-v is supported for 2.4, 4.8, and 9.6K.
SECOND
Secondary channel operation allows the DSU/CSU to establish a separate lower-speed data
circuit with the OCU-DP port. When synchronized, this special circuit can be used for testing
and maintenance of the main circuit, or for transmission of other low-speed data. The settings
are on and off.
The secondary channel is transported in the 8th bit position of the DS0 time slot to which the
OCU-DP is assigned. Table 17-3 shows the secondary channel rate associated with the various
primary port rates supported by the card. For a further description of the secondary channel
function, refer to Pub 62310 and TA-TSY 000077 and TA-TSY 000083.
Table 17-3. OCU-DP Primary and Secondary Channel Rates
USER LB
The User Loopback (USER LB) is a specialized code conversion function that is only relevant
in Taiwan and some other countries in the Far East. The options are d and o, neither of which
has any effect in North America.
Primary Port Rate Secondary Channel Rate
56 kbps 2666 bps
19.2 kbps 1,066 bps
9.6 kbps 533 bps
4.8 kbps 266 bps
2.4 kbps 133 bps