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Chapter 3
Programming Examples
Reading Trace Data Using 32-bit Real Format (RS-232)
Reading Trace Data Using 32-bit Real Format (RS-232)
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/* Reading Trace Data using 32-bit Real Format (RS-232) */
/* */
/* This example is for the E44xxB ESA Spectrum Analyzers */
/* and E740xA EMC Analyzers. */
/* */
/* This C programming example does the following. */
/* The SCPI instrument commands used are given as */
/* reference. */
/* */
/* - Opens an RS-232 session at COM1/COM2 */
/* - Clears the Analyzer */
/* - Resets the Analyzer */
/* *RST */
/* - Set the input port to the 50 MHz amplitude reference */
/* CAL:SOUR:STAT ON */
/* - Query for the number of sweep points (for firmware */
/* revision A.04.00 and later). Default is 401. */
/* SENS:SWE:POIN? */
/* - Calculate the number of bytes in the header */
/* - Set the analyzer to single sweep mode */
/* INIT:CONT 0 */
/* - Sets the analyzer center frequency and span to 50 MHz */
/* SENS:FREQ:CENT 50 MHZ */
/* SENS:FREQ:SPAN 50 MHZ */
/* - Specify 10 dB per division for the amplitude scale in */
/* and dBm Units */
/* DISP:WIND:TRAC:Y:SCAL:PDIV 10 dB */
/* UNIT:POW DBM */
/* - Set the analyzer trace data to 32-bit Real */
/* FORM:DATA: REAL,32 */
/* - Set the binary order to swap */
/* FORM:BORD SWAP */
/* - Trigger a sweep */
/* INIT:IMM */
/* - Check for operation complete */
/* *OPC? */
/* - Calculate the number of bytes in the trace record */
/* - Set VISA timeout to 60 seconds, to allow for slower */
/* transfer times caused by higher number of sweep points */
/* at low baud rates. */
/* - Set VISA to terminate read after buffer is empty */