MT9074 Datasheet, PDF (78/122 Pages) Mitel Networks Corporation – T1/E1/J1 Single Chip Transceiver

MT9074
Advance Information
Bit
Name
Functional Description
7
NRZ
NRZ Format Selection. Only used in the digital framer only mode (LIU is
disabled). A one sets the MT9074 to accept a unipolar NRZ format input
stream on RxA as the line input, and to transmit a unipolar NRZ format
stream on TxB. A zero causes the MT9074 to accept a complementary pair
of dual rail inputs on RxA/RxB and to transmit a complementary pair of dual
rail outputs on TxA/TxB.
6-4
TX2-0
Transmit pulse amplitude. Select the TX2 –TX0 bits according to the line
type, value of termination resistors (RT), and transformer turns ratio used
TX2 TX1 TX0 Line Impedance(ohms) RT(ohms) Transformer Ratio
000
120
0
1:2
001
120
0
1:1
010
120
15
1:2
011
120/75
12.1
1:2
100
75
0
1:2
101
75
0
1:1
111
75
9.1
1:2
111
75/120
12.1
1:2
After reset these bits are zero.
3
REDBL
Receive Equalizer Disable. If one the receive equalizer is turned off. If zero,
the receive equalizer is turned on and will compensate for loop length
automatically.
2-0
RES2-0
Receive Equalization Select. Setting these pins forces a level of
equalization of the incoming line data.
RES2
RES1
RES0 Receive Equalization
0
0
0
none
0
0
1
6dB
0
1
0
12dB
0
1
1
18dB
1
0
0
24dB
1
0
1
reserved
1
1
0
reserved
1
1
1
reserved
These settings have no effect if REDBL is set to zero.
Table 94 - LIU Control Word (E1)
(Page 1, Address 1FH)
78