Returns trace header information for the trace. Use the commands in the MMEMory subsystem to store and recall traces from the instrument memory. The response begins with an ASCII header. The header specifies the number of following bytes. It looks like #AX, where A is the number of digits in X and X is the number of bytes that follow the header. Parameters are returned in comma-delimited ASCII format. Each parameter is returned as “NAME=VALUE[ UNITS],” Note that currently only Trace A header is retrieved. Valid parameters are shown in
“Cable & Antenna Parameter Names”.
When in dual overlay mode, a second set of data is returned when no parameter is passed in with the query. The response starts with an ASCII header that is exactly like the one described above. The header will have the format #AX where A is the number of digits in X and X is the number of bytes that follow the header. When there are two sets of data, a second ASCII header will trail the first header. The second header will have the format $AX where A is the number of digits in X and X is the number of bytes in the first set of data. The starting point of the second set of data can be found by subtracting the total byte size of the first set of data from the byte size located in the first header. For example, if the first header is #540000 and the second header is $41000, the beginning of the second set of data is 40000(size of total packet size)-1000(size of first data set). Alternatively, the two headers can be skipped and after 551 points are read from the first set, the second set starts.
