Signal Output

Instrument network (INET)

configuration, consult appropriate manual(s) for the controller device (the HP 5890 is never a controller).

An instrument

Addresses

An instrument is a device, housing together a collection of functions, and having a single model number. It has a single pair (IN and OUT) of INET cable connections.

The INET controller assigns each instrument a unique address, in order, around the loop. Thus, addresses correspond to the physical order of connections around the loop.

Note that the controller usually is also an instrument in that it has capability of performing various analytical tasks (for example, integration).

Data or a command message destined for a particular instrument is labelled with the corresponding address for the instrument.

Setpoints

The controller passes setpoints among INET instruments (including itself), and to and from local storage. Setpoints are grouped according to the instrument to which they belong, and labelled with the corresponding INET address. Setpoint traffic is automatic, once appropriate commands are entered at the controller.

If an instrument receives setpoints intended for a different instrument because of an address error, it rejects them, causing the controller to print an error message.

Generally, each instrument provides a means for entering its own setpoints (i.e., a keyboard or control panel). The HP 19405A S/ECM is an exception: its setpoints are defined through the controller.

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