CX28394/28395/28398
3.0 Registers
Quad/x16/Octal—T1/E1/J1 Framers
3.14 Bit-Oriented Protocol Registers
3.14 Bit-Oriented Protocol Registers
The Bit Oriented Protocol (BOP) transceiver sends and receives BOP messages, including ESF Yellow Alarm.
These messages consist of repeated 16-bit patterns with an embedded 6-bit codeword. The BOP message
channel is configured to operate over the same channel selected by the DL1 Time Slot Enable Register
[DL1_TS; addr 0A4]. The channel must be configured to operate over the FDL channel in order for BOP
messages to convey Priority, Command, and Response codeword messages according to ANSI T1.403,
Section 9.4.1. Therefore, DL1 must be configured and enabled to allow BOP operation, as described in
Table 3-22.
Table 3-22. DLI Configuration for T1-ESF, FDL
Datalink Configuration Registers
Value
0 × 40
Description
Enabling odd frames, Fbit (T1)
DL1_TS [addr 0A4]
DL1_BIT [addr 0A5]
DL1-CTL [addr 0A6]
RDL1_FFC [addr 0A7]
TDL1_FEC [addr 0AB]
0 × 00
Select bits to use in time slot.
0 × 03
Select normal FIFO mode, FCS, Tx enabled, Rx enabled.
###### is the threshold for receiver FIFO near full.
###### is the threshold FIFO near empty.
00######
00######
The precedence of transmitted BOP messages with respect to current DL1 transmit activity is configurable
[TBOP_MODE; addr 0A0]. BOP messages can also be transmitted during E1 mode, although the 16-bit
codeword pattern has not currently been adopted as an E1 standard. BOP message format:
0xxxxxx0 11111111 (transmitted right to left)
[543210] 6-bit codeword
0A0—Bit Oriented Protocol Transceiver (BOP)
7
6
5
4
3
2
1
0
RBOP_START
RBOP_INTEG
RBOP_LEN[1]
RBOP_LEN[0]
TBOP_LEN[1]
TBOP_LEN[0] TBOP_MODE[1] TBOP_MODE[0]
RBOP_START
RBOP_INTEG
BOP Receiver Enable—When active, BOP receiver searches FDL channel for data that
matches a 16-bit pattern in the form of 0xxxxxx011111111, where xxxxxx equals a 6-bit
codeword. Otherwise, BOP receiver is disabled.
0 = disabled
1 = BOP receiver enable
RBOP Integration—Requires receipt of two identical consecutive 16-bit patterns (without
errors or gaps between patterns) to validate a single codeword. In this case, an errored
codeword does not increment the pattern count. RBOP integration must be enabled to meet
codeword detection criteria while receiving 1E-3 bit error ratio. RBOP_INTEG adds at least
one to the number of successive 16-bit patterns needed to qualify receipt of BOP message (2 in
a row counts as 1 pattern, 11 in a row counts as 10, and 26 in a row counts as 25).
0 = no integration
1 = RBOP integration
100054E
Conexant
3-71
CONEXANT [ CONEXANT SYSTEMS, INC ]
