mk50h27 STMicroelectronics, mk50h27 Datasheet - Page 11

• Manufacturer Part Number: mk50h27
• Description: Signalling System 7 Link Controller
• Manufacturer: STMicroelectronics

and receiver descriptor rings, etc. The starting
address for the Initialization block, IADR, is de-
fined in the CSR2 and CSR3 registers inside the
MK50H27.
3.2.3 Signal Unit Repertoire
The frame format supported by the MK50H27 is
shown in Table A. Each signal unit (SU) may
consist of a programmable number of leading flag
patterns (01111110), Backward Sequence Num-
ber, Backward Indicator Bit, Forward Sequence
Number, Forward Indicator Bit, Lenght Indicator
Field, followed by Signalling Information Octet,
Service Information Field, or Status Field, de-
pending on SU type, and then ended with a CK
(CRC) of either 16 or 32 bits, and a trailing flag
pattern. The number of leading flags transmitted
is programmable through the Mode Register in
the Initialization Block. Received signal units may
have as few as one flag between adjacent signal
units
The symbols and definitions for the signal unit
types handled by the MK50H27 are:
TABLE A - MK50H27 Signal Unit Repertoire
NAME
MSU
LSSU
FISU
F
FSN
BSN
FIB
BIB
LI
X
PRI
SIO
SIF
SF
CK
DEFINITION
Message Signal Unit
Link Status Signal Unit
Fill In Signal Unit
Flag Sequence (01111110)
Forward Sequence Number
Backward Sequence Number
Forward Indicator Bit
Backward Indicator Bit
Lenght Indicator
Reserved - programmed as zeroes
Priority Indication (JT-Q703 only)
Signalling Information Octe
Service Information Field
Status Field
Check bit Sequence (CRC)
MK50H27
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