Fluke PM-3380B Acquiring Traces, Channels and memory registers Example Send -- FORMat INT,16

2 - 6 GETTING STARTED WITH SCPI PROGRAMMING

2.4 Acquiring Traces

Trace acquisitions are started via the INITiate commands. A single acquisition is done by sending a single INITiate command. Continuous acquisitions are done by sending the INITiate:CONTinuous ON command.

The TRACe? query allows you to acquire a trace of signal samples from one of the following sources:

•An input channel, e.g., CH2 (input channel 2).

•A trace area in a memory register, e.g., M2_3 (Memory register 2, trace 3).

The number of trace samples (acquisition length) can be specified using the TRACe:POINts command. If your instrument has standard memory, you can specify 512, 2048, 4096, or 8192 trace samples. If your instrument has extended memory, you can specify 512, 8192, 16384, or 32768 trace samples. A TRACe:POINts command specifies the acquisition length for all channels and memory registers.

Example: Send --> TRACe:POINts CH1,8192 ’Selects 8192 sample points for all traces

The number of trace sample bits can be specified using the FORMat command. This gives you the possibility to define samples of 8 bits (1 byte) or 16 bits (2 bytes). A FORMat command specifies the number of sample bits for all

channels and memory registers.
Example: Send --> FORMat INT,16	’Formats 16-bits samples

The format of the trace response data is as follows:

# n x . . x f b . . . . . b s <NL>

		NewLine code (10 decimal)
		checksum byte over all trace bytes
		trace sample data bytes (see Note)
		trace data format byte (see Note)
		number of trace bytes (fbb...bbs)
		number of digits of x..x
Note:	If f=8 decimal, each trace sample is one byte (8 bits).
	If f=16 decimal, each trace sample is two bytes (16 bits), i.e., most significant byte
	(msb) + least significant byte (lsb).

Example:

# 4 1 0 2 6 <16> <msb 1> <lsb 1> . . . <msb 512> <lsb 512> <checksum> <10>

trace sample 512 trace sample 1 decimal 16

number of trace bytes (N) number of digits of N