BT8375 CONEXANT [Conexant Systems, Inc], BT8375 Datasheet - Page 165

• Manufacturer Part Number: BT8375
• Description: single chip transceivers for T1/E1 and Integrated Service Digital Network (ISDN) primary rate interfaces
• Manufacturer: CONEXANT [Conexant Systems, Inc]

Bt8370/8375/8376
Fully Integrated T1/E1 Framer and Line Interface
3.8 Receiver Registers
Unused bits indicated by a dash (
effect.
RAMI
RABORT
RFORCE
N8370DSE
040—Receiver Configuration (RCR0)
RAMI
7
Receive AMI Encoded Inputs—Disables B8ZS/HDB3 decoding for AMI-formatted
RTIP/RRING receive signals. Otherwise, the ZCS decoder replaces the 000VB0VB code
(B8ZS) with 8 zeros in T1 mode, or replaces the X00V code (HDB3) with four zeros in E1
mode; where B is a normal AMI pulse, V is a bipolar violation, and X is a “don't-care.”
Regardless of RAMI setting, receipt of a ZCS signature is always detected and reported in
ZCSUB status [RSTAT; addr 021].
Abort/Disable RX Offline Framer—When set, the offline framer ignores reframe requests
from the online framer (RLOF) and aborts any in-progress RLOF reframe request. Loss of
Frame status [RLOF; addr 047] is not affected. While RABORT remains set, the offline framer
only responds to processor forced reframes (RFORCE). This allows the processor to manually
control reframe criteria and prevent changes in the current receive frame alignment. RABORT
is typically set only during unframed operation.
Force RX Reframe—Forces the offline framer to perform a single reframe according to
selected receive framer mode. RFORCE is automatically cleared when the offline framer
acknowledges the request [FSTAT; addr 017]. The processor typically does not need to force
the reframe since the online framer reframe request (RLOF) is active whenever reframe criteria
(RLOFD–A) is met. However, the processor may force a reframe if the frame or CRC error
ratios indicate the framer might have aligned to a duplicated frame alignment pattern.
RABORT
6
RFORCE
—
5
) are reserved and should be written to 0. Writing to reserved bits has no
0 = receive B8ZS/HDB3 line format
1 = receive AMI line format
0 = normal framer operation
1 = framer disabled
0 = no effect
1 = force RX reframe
RLOFD
4
Conexant
RLOFC
3
RLOFB
2
RLOFA
1
3.8 Receiver Registers
RZCS
0
3-47