MT8981D Datasheet, PDF (6/14 Pages) Mitel Networks Corporation – ISO-CMOS ST-BUS™ FAMILY Digital Switch

MT8981D ISO-CMOS
No Corresponding Memory
- These bits give 0s if read.
Per Channel
Control Bits
7
6
5
4
3
2
1
0
BIT
NAME
DESCRIPTION
2
Message When 1, the contents of the corresponding location in Connection Memory Low are
Channel output on the location’s channel and stream. 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.
1
Unused
0
Output If the ODE pin is high and bit 6 of the Control Register is 0, then this bit enables the
Enable 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.
Figure 5 - Connection Memory High Bits
(unused)
Stream
Address
Bits
Channel
Address
Bits
7
6
5
4
3
2
1
0
BIT
NAME
DESCRIPTION
7
(Unused) Must be a 0.
6-5*
Stream The number expressed in binary notation on these 2 bits is the number of the ST-BUS
Address stream for the source of the connection. Bit 6 is the most significant bit. e.g., if bit 6 is 1,
Bits* and bit 5 is 0, then the source of the connection is a channel on STi2.
4-0*
Channel The number expressed in binary notation on these 5 bits is the number of the channel
Address which is the source of the connection (The ST-BUS stream where the channel lies is
Bits* defined by bits 6 and 5.). Bit 4 is the most significant bit. e.g., if bit 4 is 1, bit 3 is 0, bit 2 is
0, bit 1 is 1 and bit 0 is 1, then the source of the connection is channel 19.
*If bit 2 of the corresponding Connection High location is 1 or if bit 6 of the Control Register is 1, then these entire
8 bits are output on the channel and stream associated with this location. Otherwise, the bits are used as
indicated to define the source of the connection which is output on the channel and stream associated with this
location.
Figure 6 - Connection Memory Low Bits
2-22