DS21455 Maxim Integrated Products, DS21455 Datasheet - Page 88

• Manufacturer Part Number: DS21455
• Description: Network Controller & Processor ICs Quad E1-T1-J1 Single -Chip Transceiver (S
• Manufacturer: Maxim Integrated Products

Specifications of DS21455

• Product: Framer
• Number Of Transceivers: 4
• Data Rate: 64 Kbps
• Supply Voltage (max): 3.465 V
• Supply Voltage (min): 3.135 V
• Supply Current (max): 328 mA
• Maximum Operating Temperature: + 70 C
• Minimum Operating Temperature: 0 C
• Mounting Style: SMD/SMT
• Package / Case: BGA

15.2 Path Code Violation Count Register (PCVCR)
15.2.1 T1 Operation
The path code violation count register records either Ft, Fs, or CRC6 errors in T1 frames. When the
receive side of a framer is set to operate in the T1 ESF framing mode, PCVCR will record errors in the
CRC6 codewords. When set to operate in the T1 D4 framing mode, PCVCR will count errors in the Ft
framing bit position. Via the ERCNT.2 bit, a framer can be programmed to also report errors in the Fs
framing bit position. The PCVCR will be disabled during receive loss of synchronization (RLOS = 1)
conditions. See
Table 15-3. T1 Path Code Violation Counting Arrangements
15.2.2 E1 Operation
The PCVCR records CRC-4 errors. Since the maximum CRC-4 count in a one-second period is 1000, this
counter cannot saturate. The counter is disabled during loss of sync at either the FAS or CRC-4 level; it
will continue to count if loss of multiframe sync occurs at the CAS level.
The PCVCR1 is the most significant word and PCVCR2 is the least significant word of a 16-bit counter
that records path violations (PVs).
Register Name:
Register Description:
Register Address:
Bit #
Name
Default
Bits 0 to 7/Path Code Violation Counter Bits 8 to 15 (PCVC8 to PCVC15). PCVC15 is the MSB of the 16-bit path code
violation count.
Register Name:
Register Description:
Register Address:
Bit #
Name
Default
Bits 0 to 7/Path Code Violation Counter Bits 0 to 7 (PCVC0 to PCVC7). PCVC0 is the LSB of the 16-bit path code
violation count.
FRAMING MODE
PCVC15
PCVC7
ESF
D4
D4
7
0
7
0
Table 15-3
PCVC14
PCVC6
PCVCR1
Path Code Violation Count Register 1
44h
PCVCR2
Path Code Violation Count Register 2
45h
6
6
0
0
for a detailed description of exactly what errors the PCVCR counts.
COUNT Fs ERRORS?
PCVC13
PCVC5
5
0
5
0
Don’t Care
Yes
PCVC12
No
PCVC4
4
0
4
0
88 of 270
PCVC11
PCVC3
3
0
3
0
Errors in the Ft Pattern
Errors in Both the Ft and Fs Patterns
Errors in the CRC6 Codewords
WHAT IS COUNTED IN THE PCVCRs
PCVC10
PCVC2
2
0
2
0
PCVC1
PCVC9
1
0
1
0
PCVC8
PCVC0
0
0
0
0