tfra08c13 ETC-unknow, tfra08c13 Datasheet - Page 60

• Manufacturer Part Number: tfra08c13
• Description: Tfra08c13 Octal T1/e1 Framer
• Manufacturer: ETC-unknow

TFRA08C13 OCTAL T1/E1 Framer
CEPT Time Slot 0 FAS/NOT FAS Control Bits
60
START OF CRC-4 DOUBLE MULTIFRAME:
• BASIC FRAME ALIGNMENT FOUND, OR,
• CRC-4 MULTIFRAME ALIGNMENT FOUND.
START FRAME 1 OF 32 IN DMF.
CRC-4 DOUBLE MULTIFRAME
SYSTEM ACCESS Sa STACK (SASS) INTERVAL:
Figure 16. Transmit and Receive Sa Stack Accessing Protocol
(DMF): 32 FRAMES
1)
2)
3)
31 FRAMES
TRANSMIT FRAMER UNIT TRANSMITS TO THE LINE
THE DATA IN THE TRANSMIT Sa STACK WRITTEN DURING
THE PREVIOUS SASS INTERVAL.
THE SYSTEM CAN UPDATE THE TRANSMIT Sa STACK
REGISTERS FOR TRANSMISSION IN THE NEXT CRC-4
DOUBLE MULTIFRAME.
THE SYSTEM CAN READ THE RECEIVE Sa STACK REGISTERS
TO ACCESS THE Sa BITS EXTRACTED DURING THE PREVIOUS
VALID (IN MULTIFRAME ALIGNMENT) DOUBLE CRC-4
MULTIFRAME.
SYSTEM ACCESS IS DISABLED DURING THIS INTERVAL:
1)
2)
3)
4)
5)
6)
7)
THE INTERNAL TRANSMIT Sa STACK IS UPDATED
FROM THE FRAMER UNIT’S 10-byte TRANSMIT STACK CONTROL
REGISTERS DURING THIS 1-FRAME INTERVAL.
ACCESS TO THE STACK CONTROL REGISTERS IS DISABLED
DURING THIS 1-FRAME INTERVAL.
ONCE LOADED, THE INFORMATION IN THE INTERNAL TRANSMIT
Sa STACK IS TRANSMITTED TO THE LINE DURING THE NEXT
CRC-4 DOUBLE MULTIFRAME, ALIGNED TO THE CRC-4 MULTIFRAME.
IF THE TRANSMIT Sa STACK IS NOT UPDATED, THEN THE
CONTENT OF THE TRANSMIT Sa STACKS IS RETRANSMITTED
TO THE LINE.
THE SYSTEM READ-ONLY RECEIVE STACK IS UPDATED FROM
THE INTERNAL RECEIVE STACK INFORMATION REGISTERS.
IN NON-CRC-4 MODE, THE RECEIVE Sa STACK EXTRACTING
CIRCUITRY ASSUMES AN ARBITRARY DOUBLE 16-FRAME MULTIFRAME STRUCTURE
(32 FRAMES), AND DATA IS EXTRACTED ONLY IN THE FRAME ALIGNED STATE.
IN CRC-4 MODE, THE RECEIVE Sa STACK INFORMATION IS ALIGNED
TO A CRC-4 DOUBLE MULTIFRAME STRUCTURE (32 FRAMES), AND THE
DATA IS EXTRACTED ONLY IN CRC-4 MULTIFRAME ALIGNED STATE.
1 FRAME
SYSTEM ACCESS Sa STACK INTERVAL
INTERNAL Sa STACK UPDATE INTERVAL
CRC-4 DOUBLE MULTIFRAME: 32 FRAMES
(continued)
31 FRAMES
Preliminary Data Sheet
Lucent Technologies Inc.
1-FRAME INTERVAL
Lucent Technologies Inc.
October 2000
5-3911(F).c