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Device Messages R&S FSH-K1
1157.3564.12 4 E-8
Device Messages
The remote control command set of the R&S FSH can be grouped into three categories:
•
SET commands
SET commands are used to program parameters of the instrument like
center frequency, span, etc.
•
GET commands
GET commands are used to query current settings and data from the instrument like
center frequency, marker, trace data, etc.
•
CMD commands
CMD commands are used to initiate an action or a state transition in the instrument like
marker-to-peak, preset, remote state, etc.
Acknowledge Response <ack>
After receiving a SET, GET or CMD command the R&S FSH responds with an “acknowledge”
message. The acknowledge message consists of an ASCII digit (“0” for no error) followed by a Carriage
Return <cr>. The response message indicates if the command or parameter is valid.
A second acknowledge response is generated after the command parameter.
<ack> response:
“0” No Error.
“1”
Syntax Error. This response is generated when the command sent to the instrument is not
known or when the timeout on data reception expired. It is also generated, when the
parameter or value for the command are in the wrong data format.
“2”
Execution Error. The command sent is not allowed in the current measurement mode.
“3”
Dataset Storage Full. This response is generated when the dataset storage is full.
“4”
Not Allowed. In the current state of the R&S FSH setting this parameter or value is not
allowed.
“5”
Out Of Range. The parameter value is out of range and cannot be programmed.
Timeout
To prevent any lockups in the communication between PC and instrument the data transfer via the
serial interface is monitored by the R&S FSH. There is a timeout time of 60 seconds on every byte
received by the instrument. When the time between 2 bytes in a command or parameter send exceeds
60 seconds the R&S FSH will respond with a ‘Syntax Error’ acknowledge message (“1”<cr>).
Note: When using remote control commands and the sweep time is less than 30 ms (e.g. Zero
span) the measurement will stop until the complete command is received (in this case all
interrupts are switched off due to the processing of all data points).