MT90812 Mitel Networks Corporation, MT90812 Datasheet - Page 54

• Manufacturer Part Number: MT90812
• Description: Integrated Digital Switch (IDX)
• Manufacturer: Mitel Networks Corporation

MT90812
21.0 Connection Memory Bits
Locations in the Connection Memory are associated with the local TDM output streams and the Expansion Bus
streams. It also determines whether individual output channels are in Message Mode, allows individual output
channel to go into a high-impedance state and specifies the gain control for the outgoing channels. Refer to
Section 5.2, “Data Memory and Connect Memory” for further description.
21.1
50
7-3
1-0
Bit
2
1
0
Message Channel/
Connection Memory High
address locations
G4,G3, G2, G1,
(for Conference
locations other
locations other
Output Enable
Inversion Bit
Conference
than 60-6E)
than 60-6E)
Attenuation
NS1-NS0
(address
(address
Channel
60-6E)
Name
CST
G0
Defines gain from +3 to -27 dB in steps of 1dB, as well as - dB for the outgoing
channel
When 1, the contents of the corresponding location in Connection Memory Low are
output on the location’s channel. When 0, the contents of the corresponding
location in Connection Memory Low act as an address for the Data Memory and so
determine the source of the connection to the location’s channel and stream.
Conference Inversion Bit: (For Conference address locations 60-6E) The inversion
bit allows for every other channel in a conference to be inverted. This reduces noise
due to reflections and line impedance mismatch.
This bit is used to select minimum(low) or constant(high) delay, on a per channel
basis.
If the ODE pin is high and bit 5 of the Control Register is 0, then this bit enables the
output driver for the location’s channel and stream. This allows individual channels
on individual streams to be made high-impedance, allowing switching matrices to
be constructed. A 1 enables the driver and a 0 disables it.
Channel Noise Suppression
00 = no noise suppression
01 = 9/4096 (A-Law), 9/8159 (u-Law)
10 = 16/4096 (A-Law), 16/8159 (u-Law)
11 = 32/4096 (A-Law), 32/8159 (u-Law)
G4
7
G3
6
0000 = +3 dB
0001 = +2 dB
0010 = +1 dB
0011 = 0 dB
0100 = -1 dB
0101 = -2 dB
0110 = -3 dB
0111 = -4 dB
1000 = -5 dB
1001 = -6 dB
1010 = -7 dB
1011 = -8 dB
1100 = -9 dB
1101 = -10 dB
1110 = -11 dB
1111 = -12 dB
G2
5
G1
4
G0
3
MSG/
INV
2
Description
10000 = -13dB
10001 = -14dB
10010 = -15dB
10011 = -16dB
10100 = -17dB
10101 = -18 dB
10110 = -19 dB
10111 = -20 dB
11000 = -21 dB
11001 = -22 dB
11010 = -23 dB
11011 = -24 dB
11100 = -25 dB
11101 = -26 dB
11110 = -27 dB
11111 = -
CST/
NS1
1
OE/
NS0
0
dB
Advance Information