Rohde & Schwarz SMBV100A, Manual

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Remote Control Basics
R&S
®
SMBV100A
398 Operating Manual 1407.6062.32 ─ 08
ASRL[0-9][::INSTR]
where
ASRL[0-9]
determines the number of the COM port on the controller side, that
has to be used for the serial connection.
Access via a bluetooth device requires the entry of the bluetooth pin in addition (see
​
chapter 5.2.3.16, "Security" , on page 128).
To enable an error-free and correct data transmission, the parameters of the generator
and the controller must have the same setting. The serial interface is preset for a baud
rate 115200, no parity and one stop bit. The parameters can be manually changed in
"Remote Channel Settings" dialog (see
​
chapter 5.2.3.14, "Remote Channel Set-
tings" , on page 124).
6.1.6 GPIB Interface (IEC/IEEE Bus Interface)
To be able to control the instrument via the GPIB bus, the instrument and the controller
must be linked by a GPIB bus cable. A GPIB bus card, the card drivers and the program
libraries for the programming language used must be provided in the controller. The con-
troller must address the instrument with the GPIB bus address (see
​
chapter 6.1.6.2,
"GPIB Instrument Address" , on page 399).
Characteristics
The GPIB interface is described by the following characteristics:
●
Up to 15 instruments can be connected
●
The total cable length is restricted to a maximum of 15 m; the cable length between
two instruments should not exceed 2m.
●
A wired "OR"-connection is used if several instruments are connected in parallel,
since the slowest instrument determines the speed.
Any connected IEC bus cable must be terminated by an instrument or controller.
6.1.6.1 GPIB Interface Messages
Interface messages are transmitted to the instrument on the data lines, with the attention
line (ATN) being active (LOW). They are used for communication between the controller
and the instrument and can only be sent by a computer which has the function of a GPIB
bus controller. GPIB interface messages can be further subdivided into:
●
Universal commands : act on all instruments connected to the GPIB bus without
previous addressing
●
Addressed commands : only act on instruments previously addressed as listeners
Universal Commands
Universal commands are encoded in the range 10 through 1F hex. They affect all instru-
ments connected to the bus and do not require addressing.
Remote Control Interfaces and Protocols