Envision Peripherals NV3128 manual POINT-TO-POINT Connection Rules, Multidrop Connection Rules

On older systems, DIP switches on the Command Interpreter establish the logical ID for each of the two levels and also configure the partition parameters. On newer systems with the Universal Control module, levels and partitions are set up using UniDiag.

3.1.1POINT-TO-POINT CONNECTION RULES:

1.If Requested Destination is in use as a source:

Findalldestinations,breakconnectionsandtristate(turnoff)theports.

2. If Requested Destination is already tied to Source

Find all the Destination ports to which that Source port is tied. Break all connections between that Source and its Destinations. Tristate Source Port and all its Destinations.

3. If requested Source is in use as a Destination

Find all Sources tied to that port . Break those connections and tristate the Source ports.

4.Configure Source and Destination ports and make the forward and reverse crosspointconnections.

3.1.2MULTIDROP CONNECTION RULES

A connection in which a single source connects multiple destinations is always addressed on Level II. The first destination connected is the controlled device with answer-back capability. The received signals at all subsequent port connections are not routed.

1.If requested Source is currently driving other Destinations: tristate the response line of the requested Destination port.

2.If Requested Destination is in use as a source:

Findalldestinations,breakconnectionsandtristate(turnoff)theports. 3. If requested Source is in use as a Destination

Find all Sources tied to that port . Break those connections and tristate the Source ports.

NV3128 RS-422A Machine Control Data Routing Switch 3-4