MT8910-1 Mitel Networks Corporation, MT8910-1 Datasheet - Page 7

• Manufacturer Part Number: MT8910-1
• Description: CMOS St-bus Family Digital Subscriber Line Interface Circuit
• Manufacturer: Mitel Networks Corporation

Preliminary Information
T1.601-1988 standards. The activation sequence for
the DSLIC is mode dependent and is outlined in
Figures 6a) and b).
In the LT mode, the request for activation can be
initiated in two ways. Setting the start/stop bit in the
Control Register 1 will result in the generation of a
repeated pattern of four +3 symbols followed by four
-3 symbols producing a 10 kHz activation tone (TL)
for 3 milliseconds. The DSLIC can also be activated
by receiving a 10 kHz activation tone from the NT
(TN).
progression through the state machine follows the
algorithm as shown in Figure 6a.
In the NT mode, the request for activation can be
initiated in two ways. Setting the start/stop bit in the
Control Register 1 will result in the generation of a
repeated pattern of four +3 symbols followed by four
-3 symbols resulting in the transmission of the NT
activation tone (TN).
activated by receiving TL from the LT to which the
NT will respond with its own activation tone (TN).
Progression through the state machine will follow the
algorithm as shown in Figure 6b.
During the activation sequence, there is an extensive
exchange of signals between the LT and the NT.
T0 = 15 sec timer
T1 = 480 ms timer
Expiry of T0
ST.T3
Once the NT has generated a tone,
Awaiting Reply
Tx-TL (3ms)
Alerting
Tx-SL0
ST.T1
Figure 6a - Activation/Deactivation State Diagram - LT Mode
The DSLIC can also be
Expiry of
T1
RCV TN
T2 = 40 ms timer
T3 = 520 ms timer
STP.T1
ST.T0
LAR
EC Training
MRST Pin
Full Reset
Framing
Tx-SL0
Awake
Tx-SL2
Tx-SL3
Active
Tx-SL1
Tx-SL0
End SN1
EC
Converged
RCV TN
ST.T0
SFS
STP.T0
This handshaking of information is required to allow
individual transceivers to train both their echo
cancellers and decision feedback equalizers.
possible signals are described below.
•
•
•
•
•
BFS Lost > 480ms
Expiry of T0
Expiry of T0
TN:
SN0:
SN1:
SN2:
SN3:
Expiry
Expiry of T2
RCV TN
or LDR
ST.T0
STP.T2
ST.T3
Note
1
A 10 kHz activation tone sourced by the
NT which is generated by sending a
continuous pattern of four +3 symbols
followed by four -3 symbols.
SN0 is a no signal condition which is
used to indicate to the LT that the NT
has finished training its echo canceller.
An NT generated signal consisting of a
framed (but not superframed),
scrambled 2B1Q signal which carries all
1s in the B-, D- and M-channels. This
signal is used to train the NT’s echo
canceller.
An NT generated signal consisting of a
framed (but not superframed),
scrambled 2B1Q signal which carries all
1s in the B-, D- and M-channels. This
signal is used to train the LT’s DFE.
An NT generated signal consisting of a
fully framed and superframed scrambled
2B1Q signal which carries information in
all the B-, D- and M-channels.
of T0
: Loss of received signal will result in loss of sync.
ST.Tx = Start Timer x
STP.Tx = Stop Timer x
LAR = Local Activation Request
LDR = Local Deactivation Request
SFS = Superframe Synchronization Acquired
RCV Reset
Tx-SL0
1
ST.T3
Pending Deact.
Tx-SL0
(Loss of
signal and
LDR),
ST.T2
STP.T3
MT8910-1
(Loss of signal
and LDR) or
Expiry of T3
All
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