tmxf28155 ETC-unknow, tmxf28155 Datasheet - Page 516

• Manufacturer Part Number: tmxf28155
• Description: Tmxf28155 Super Mapper 155/51 Mbits/s Sonet/sdh X28/x21 Ds1/e1
• Manufacturer: ETC-unknow

155/51 Mbits/s SONET/SDH x28/x21 DS1/E1
21 28-Channel Framer Block Functional Description
If the Tx stack empty bit was 0 at the beginning of the CEPT double multiframe, then the bit will be set to 1, indicat-
ing a request for new Sa bits.
When enabled using the FRM_ASRC
ment has been reached. For CEPT links, only BFA is required for insertion. For CEPT CRC-4 links, both BFA and
MFA need to be valid. This affects the insertion of Sa bits and the reporting of stack empty to the host. There is
another configuration bit FRM_TXCRCSM
is active (FRM_TXCRCSM).
Before enabling a link for CEPT format, the host should initialize the stack and set the Tx stack empty bit to 0. If not,
the data link block will transmit the reset state of the stack which is arbitrary.
21.22.13 Transmit Data Link Stack Idle Modes
21.22.14 SLC -96, DDS, or CEPT ESF Frame Alignment
For CEPT, DDS, or SLC -96 frames, loss of frame alignment is not an issue since the framer is the source of time
slot 0 or the F bits. Once a link is enabled, the frame sequence always starts at the beginning.
In the case of the system being the source of multiframe alignment, the data link block will simply deliver what is
requested.
516
D4
J-D4
J2
CMI
No data link features
T
LIN E
FD L
C LO C K
PR O C E SS O R
C LO C K
X
TR A N SM IT
F RA M E R
D AT A L IN K IN T ER R U PT
R E G IST ER S
Figure 63. Tx Data Link Block Diagram
H O S T
(Table
(Table
412) bit, the SA bits should only be inserted when the proper align-
412) which allows the CEPT CRC-4 links to insert when only BFA
TR AN S FE R
R EA D AR B ITR A TIO N L O G IC
R E Q U ES T
T DM D AT A
IN TE R N AL B U S
RE A D R EQ U E ST LO G IC
S TA C K
T D M ID
T
S YS TE M
X
S TA CK
TD M IN T ER F AC E
W RITE
R E Q U ES T
VALID
D A TA /
S TA C K WR ITE
S TA CK R E AD
R EA D
R EQ U E S T
IN TE R FA C E
(continued)
S YS TE M
R
S H A RE D
X
S TA C K
R
S Y ST EM
X
Agere Systems Inc.
May 2001
5-9027(F)r.1