Annexes
R&S
®
CMW500
271
User Manual 1173.9463.02 ─ 02
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Program messages (control command to the instrument)
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Response messages (values returned by the instrument)
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Service request (spontaneous queries of the instrument)
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Low–level control messages (see
A VXI–11 link between a controller and an instrument uses three channels: core, abort
and interrupt channel. Instrument control is mainly performed on the core channel (pro-
gram, response and low–level control messages). The abort channel is used for imme-
diate abort of the core channel; the interrupt channel transmits spontaneous service
requests of the instrument. Link setup itself is very complex. For more details refer to the
VXI–11 specification.
Fig. 8-2: VXI–11 channels between instrument and controller
The number of controllers that can address an instrument is practically unlimited in the
network. In the instrument, the individual controllers are clearly distinguished. This dis-
tinction continues up to the application level in the controller, i.e. two applications on a
computer are identified by the instrument as two different controllers.
Fig. 8-3: Remote control via LAN from several controllers
The controllers can lock and unlock the instrument for exclusive access. This regulates
access to the instrument of several controllers.
Interfaces and Connectors
