R&S SMJ100A, Operating Manual

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Remote Control Commands
R&S
®
SMJ100A
492 Operating Manual 1403.7458.32 ─ 14
xxxxxxxx Is an ASCII-coded checksum of the data part of the
WAVEFORM
tag in the file. This value is always 0 for data lists and control
lists.
The checksum for waveforms is used for detecting transmission
errors. If the
TYPE
tag contains 0 or a non-numeric value for the
checksum, it is ignored.
It is calculated in accordance with the algorithm given bellow,
where 'start' is a pointer to the first byte after the '#' character in
the
WAVEFORM
tag and 'length' is the number of bytes between
'start' and the closing curly bracket (excluding the latter; 'length'
must be divisible by 4 without a remainder):
UINT32 checksum(void *start, UINT32 length)
{
UINT32 i, result = 0xA50F74FF;
for(i=0; i < length/4; i++)
result = result ^ ((UINT32 *)start)[i];
return(result);
}
Example: {TYPE: SMU-WV,106656}
BB:ARB:WAV:TAG? 'TYPE'
Queries the content of the
TYPE
tag.
Response: 'SMU-WV,106656'
This is a valid waveform.
{CLOCK: frequency}
(mandatory for waveforms)
The tag specifies the clock frequency at which the waveform has to be output, in Hz
(on multi-segment waveforms this tag contains the maximal clock of all segments).
A query of
ARB:CLOCk?
after loading the waveform returns the value set using the
CLOCK
tag. This value can later be altered with the command
ARB:CLOCk?
.
Example: {CLOCK: 54000000}
BB:ARB:WAV:TAG? 'CLOCK'
Queries the content of the
CLOCK
tag.
Response: 54000000
The clock frequency is set to 54 MHz.
Usage: Setting only
{COMMENT: string}
The tag contains a plain text ASCII string of arbitrary length. The string is not analyzed
in the R&S
SMJ. It is used to describe the file. The string is allowed to contain all print-
able ASCII characters except the closing curly bracket.
Waveform and List Format