DS2148T+ Maxim Integrated Products, DS2148T+ Datasheet - Page 45

• Manufacturer Part Number: DS2148T+
• Description: IC LIU E1/T1/J1 5V 44-TQFP
• Manufacturer: Maxim Integrated Products
• Type: Line Interface Units (LIUs)r

Specifications of DS2148T+

• Number Of Drivers/receivers: 1/1
• Protocol: T1/E1/J1
• Voltage - Supply: 4.75 V ~ 5.25 V
• Mounting Type: Surface Mount
• Package / Case: 44-TQFP, 44-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Table 6-4. Function of ECRS Bits and RNEG Pin
NOTES:
1) RNEG outputs error data only when in NRZ mode (CCR1.6 = 1).
2) PRBS errors will always be output at PBEO independent of ECR control bits and NRZ mode and will
6.4.1 Error Counter Update
A transition of the ECUE (CCR1.4) control bit from 0 to 1 will update the ECR registers with the current
values and reset the counters. ECUE must be set back to zero and another 0 to 1 transition must occur for
subsequent reads/resets of the ECR registers. Note that the DS2148 can report errors at RNEG when in
NRZ mode (CCR1.6 = 1) by outputting a pulse for each error occurrence. The counter saturates at 65,535
and will not rollover.
ECR1 (11H): UPPER ERROR COUNT REGISTER 1
ECR2 (12H): LOWER ERROR COUNT REGISTER 2
6.5 Error Insertion
When IBPV (CCR3.1) is transitioned from a zero to a one, the device waits for the next occurrence of
three consecutive ones to insert a BPV. IBPV must be cleared and set again for another BPV error
insertion. See
When IBE (CCR3.0) is transitioned from a zero to a one, the device will insert a logic error. IBE must be
cleared and set again for another logic error insertion. See
logic error into the datastream.
(CCR1.7)
E1 or T1
(MSB)
E15
E7
not be present at RNEG.
SYMBOL
X
0
0
0
0
1
1
1
1
E15
E0
(CCR6.2)
Figure 1-3
ECRS2
E14
E6
0
0
0
0
0
0
0
0
1
POSITION
for details on the insertion of the BPV into the datastream.
ECR1.7
ECR2.0
(CCR6.1)
E13
E5
ECRS1
X
X
X
X
X
0
0
1
1
E12
(CCR6.0)
E4
ECRS0
DESCRIPTION
MSB of the 16-bit error count.
LSB of the 16-bit error count.
X
0
1
0
1
0
1
0
1
45 of 73
E11
E3
(CCR2.3)
RHBE
X
X
X
X
X
0
0
1
1
Figure 1-3
E10
E2
CVs
BPVs (HDB3 codewords not counted)
CVs + EXZs
BPVs + EXZs
BPVs (B8ZS codewords not counted)
BPVs + 8 EXZs
BPVs
BPVs + 16 EXZs
PRBS Errors
for details on the insertion of the
FUNCTION OF ECR
COUNTERS/RNEG
E9
E1
2
(LSB)
E8
E0
1
ECR1
ECR2