BT8375 CONEXANT [Conexant Systems, Inc], BT8375 Datasheet - Page 149

• 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
TIMEOUT
ACTIVE
RX/TXN
N8370DSE
Framer Search Timeout—Cleared when the offline framer transitions to its ACTIVE state. If
multiple frame candidates exist over the entire mode-dependent timeout interval (refer to
Table
or TFORCE) initiate a single search that extends to a maximum of 24 ms before TIMEOUT.
After reporting TIMEOUT, the offline framer begins another search if the reframe request
(RLOF or TLOF) is active.
Framer Active—Offline framer transitions to its ACTIVE state in response to an RFORCE or
TFORCE reframe request from the processor, or in response to an RLOF or TLOF reframe
request from the online framer.
NOTE:
RX/TX Reframe Operation—Indicates which direction the offline framer is actively searching
or most recently searched for frame alignment. RX/TXN status is updated when the offline
framer transitions to its ACTIVE state in response to a reframe request.
The offline framer remains ACTIVE until any of the following occurs:
• alignment is found (FOUND)
• the search is aborted [see RABORT; addr 040, or TABORT; addr 071]
• the search reaches its timeout interval (TIMEOUT)
• all possible frame candidates are eliminated (INVALID)
3-5), TIMEOUT is latched active-high. Processor-generated reframe requests (RFORCE
RFORCE or TFORCE does not change the current RLOF or TLOF status. RFORCE
or TFORCE is cleared by the framer transition to ACTIVE.
0 = no candidate; search active, aborted, or found
1 = framer search timeout (multiple candidates)
0 = offline framer inactive; search completed, aborted or timed out
1 = offline framer actively searching for alignment.
0 = search data from Transmit System Bus PCM Input (TPCMI)
1 = search data from receive line interface unit.
Conexant
3.6 Primary Control and Status Registers
3.0 Registers
3-31