Specifications

Introduction
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Node Addressing
The INTERBUS master device is self-configuring because INTERBUS slave
devices are auto-addressed according to their sequence in a serial ring structure.
The master identifies read/write data in terms of a node’s relative position in the ring,
not by a fixed address. The sequential location of slaves corresponds to the order of
input and output data in the master's buffer.
The ring structure uses a distributed shift register. In a single bus cycle, data from
the master to the slaves (and from the slaves to the master) is transferred. The cycle
ends when the loop back word is returned to the master. Each node is a component
on the shift register ring on which data is circulated.
The NIM’s EDS
For a particular device to be recognized on your network, a corresponding electronic
data sheet (EDS) file must be exported to your master device. This ASCII file
contains information about a device’s:
z identity—the node’s classification is presented in terms of the manufacturer code
z data size—the master’s input buffer must account for the amount of data
expected from the device
NIM Limitations
The standard STB NIB 2212 INTERBUS NIM supports up to 16 words of
INTERBUS cyclic data. It does not support the parameter communication protocol
(PCP).