ds2156gn Maxim Integrated Products, Inc., ds2156gn Datasheet - Page 83

• Manufacturer Part Number: ds2156gn
• Description: Ds2156, Ds2156l, Ds2156ln T1/e1/j1 Single-chip Transceiver Tdm/utopia Ii Interface
• Manufacturer: Maxim Integrated Products, Inc.

13.1 Line-Code Violation Count Register (LCVCR)
13.1.1
T1 code violations are defined as bipolar violations (BPVs) or excessive 0s. If the B8ZS mode is set for
the receive side, then B8ZS codewords are not counted. This counter is always enabled; it is not disabled
during receive loss-of-synchronization (RLOS = 1) conditions. Table 13-A shows what the LCVCRs
count.
Table 13-A. T1 Line Code Violation Counting Options
13.1.2
Either bipolar violations or code violations can be counted. Bipolar violations are defined as consecutive
marks of the same polarity. In this mode, if the HDB3 mode is set for the receive side, then HDB3
codewords are not counted as BPVs. If ERCNT.3 is set, then the LVC counts code violations as defined
in ITU O.161. Code violations are defined as consecutive bipolar violations of the same polarity. In most
applications, the framer should be programmed to count BPVs when receiving AMI code and to count
CVs when receiving HDB3 code. This counter increments at all times and is not disabled by loss-of-sync
conditions. The counter saturates at 65,535 and does not roll over. The bit-error rate on an E1 line would
have to be greater than 10
Table 13-B. E1 Line-Code Violation Counting Options
COUNT EXCESSIVE
E1 CODE VIOLATION SELECT
(ERCNT.0)
ZEROS?
E1 Operation
T1 Operation
Yes
Yes
No
No
(ERCNT.3)
0
1
-2
before the VCR would saturate (Table 13-B).
B8ZS ENABLED?
(T1RCR2.5)
Yes
Yes
No
No
COUNTED IN THE LCVCRs
83 of 265
BPVs
BPVs + 16 consecutive 0s
BPVs (B8ZS codewords not counted)
BPVs + 8 consecutive 0s
COUNTED IN THE LCVCRs
BPVs
CVs