mt8926ap Mitel, mt8926ap Datasheet - Page 6

• Manufacturer Part Number: mt8926ap
• Description: Iso-cmos T1 Performance Monitoring Adjunct Circuit Pmac
• Manufacturer: Mitel

MT8926
connects to DSTi1 of the PMAC and to the receive
side of the system. This allows the PMAC to perform
a payload loopback by internally connecting DSTi1 to
DSTo. In normal operation, transmit data will flow
from DSTi0 to DSTo of the PMAC to DSTi of the
MT8976/77.
PMAC RESET
The MT8926 functions may be suspended by making
the RESET input low (RESET must be high for
4-8
PCSW = Per Channel Status Word
PSW = Phase Status Word
* MT8976/77 Data unaltered by
CSTo
T1
the MT8926
LCW = Loopback Control Word
ST-BUS Transmit
ST-BUS Receive
Data Stream
Data Stream
7-5
PMAC Miscellaneous
Bit
4
3
2
1
0
Status Word
PCSW
0-2
1-3
Function
Not Used
LLDD (001)
LLED (00001)
FECV
TMR (2SEC)
BOMV
PS
W
3
PCSW
4-6
4-6
Figure 5 - CSTo Channel Allocation Versus T1 Channels
SW
PM
Figure 6 - Payload and Line Loopback Operation
7
DSTi0
DSTi1
Check-6 Error Counter
Cyclic Redundancy
Bit
Repeating
Repeating
PCSW
7
0
8-10
00001
7-9
Bit
7*
6*
5
4
3*
2
1*
0*
001
Master Status Word 1
Function
MSB
LSB
CRC
MT8926
11
YLALR
MIMIC
ALRM
RAI (ESF YELLOW)
MFSYNC
LOS
SLIP
SYN
Function
LCW
PCSW
12-14
10-12
To PMAC
Control
4 to 1 MUX
MS
W1
15
normal operation). In the reset state, data entering
the PMAC on FDLi, DSTi0 and CSTi0 will pass
through unaltered to FDLo, DSTo and CSTo
respectively.
impedance and the 1SEC output (and TMR bit) will
be low.
After the MT8976/77 has acquired frame synchroni-
zation and RESET returns high, the MT8926 will
require two superframes to acquire synchronization
and two ST-BUS frames to align to the ST-BUS.
RESET can be used to prevent DS1 interface
PCSW
16-18
13-15
7-4
3-0
Bit
CSTi1
Bipolar Violation Counter
DSTo
Errored Frame
Event Counter
Bit
7
0
EC
SE (MSB-LSB)
FE (MSB-LSB)
EF
19
Function
PCSW
20-22
16-18
Function
MSB
LSB
E8Ko will be high, IRQ will be high
LCW
0 0
0 1
1 0
1 1
BPV
From System
Control
23
PCSW
24-26
19-21
Received Bit-Oriented
DSTi0 to DSTo
DSTi1 to DSTo
00001 to DSTo (activate)
001 to DSTo (deactivate)
Bit
Message Register
2
7
0
Function
Bit
7*
6*
5*
4
3
2
1
0
CSTi1
DSTi
BOM
DSTo
Function
27
Rx
Received First
Received Last
MT8976/77
Master Status Word 2
PCSW
28-30
22-24
Function
BlAlm
FrCnt
Xst
SEI
FSI
CSI
BSI
AIS
TxB
TxA
MS
W2
31
RxA
RxB
ECLK