2-22

Figure 5 - Connection Memory High Bits

Figure 6 - Connection Memory Low Bits

BIT

NAME

DESCRIPTION

2

Message

Channel

When 1, the contents of the corresponding location in Connection Memory Low are

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

Enable

If the ODE pin is high and bit 6 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.

BIT

NAME

DESCRIPTION

7

(Unused)

Must be a 0.

6-5*

Stream

Address

Bits*

The number expressed in binary notation on these 2 bits is the number of the ST-BUS

stream for the source of the connection. Bit 6 is the most significant bit. e.g., if bit 6 is 1,

and bit 5 is 0, then the source of the connection is a channel on STi2.

4-0*

Channel

Address

Bits*

The number expressed in binary notation on these 5 bits is the number of the channel

which is the source of the connection (The ST-BUS stream where the channel lies is

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.

7

6

5

432

1

0

No Corresponding Memory

- These bits give 0s if read.

Per Channel

Control Bits

7

6

5

432

1

0

7

6

5

432

1

0

(unused)

Stream

Address

Bits

Channel

Address

Bits