HP Sander 16500C manual HP-IB Bus Addressing, Interface Select Code Selects the Interface

Models: Sander 16500C

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Programming Over HP-IB

HP-IB Bus Addressing

An instrument, therefore, may be talk-addressed, listen-addressed, or unaddressed by the controller.

If the controller addresses the instrument to talk, it will remain configured to talk until it receives:

an interface clear message (IFC)

another instrument’s talk address (OTA)

its own listen address (MLA)

a universal untalk (UNT) command.

If the controller addresses the instrument to listen, it will remain configured to listen until it receives:

an interface clear message (IFC)

its own talk address (MTA)

a universal unlisten (UNL) command.

HP-IB Bus Addressing

Because HP-IB can address multiple devices through the same interface card, the device address passed with the program message must include not only the correct instrument address, but also the correct interface code.

Interface Select Code (Selects the Interface)

Each interface card has its own interface select code. This code is used by the controller to direct commands and communications to the proper interface. The default is always "7" for HP-IB controllers.

Instrument Address (Selects the Instrument)

Each instrument on the HP-IB port must have a unique instrument address between decimals 0 and 30. The device address passed with the program message must include not only the correct instrument address, but also the correct interface select code.

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Page 42
Image 42
HP Sander 16500C manual HP-IB Bus Addressing, Interface Select Code Selects the Interface