Agilent Technologies 66lxxA manual Volt LEV Prot Curr, Voltlev 8.0 Prot 8.8 CURR?

Figure 2-1. Command Message Structure

The basic parts of the above message are:
Message Component	Example
Headers	VOLT LEV PROT CURR
Header Separator	The colon in VOLT:LEV
Data	8.0 8.8
Data Separator	The space in VOLT 8. 0 and PROT 8. 8
Message Units	VOLT:LEV 8.0 PROT 8.8 CURR?
Message Unit Separator	The semicolons in VOLT: LEV 8. 0; and PROT 8. 8;
Root Specifier	The colon in PROT 8. 8; : CURR?
Query Indicator	The question mark in CURR?
Message Terminator	The <NL> (newline) indicator. Terminators are not part of the SCPI syntax.

Parts of a SCPI Message

Headers

Headers are instructions recognized by the power module interface. Headers (which are sometimes known as "keywords") may be either in the long form or the short form.

Long Form	The header is completely spelled out, such as VOLTAGE, STATUS, and DELAY.
Short Form	The header has only the first three or four letters, such as VOLT, STAT, and DEL.

Short form headers are constructed according to the following rules:

∙ If the header consists of four or fewer letters, use all the letters. (DFI LIST)

∙If the header consists of five or more letters and the fourth letter is not a vowel (a,e,i,o,u), use the first four

letters. (CURRent STATus)

∙If the header consists of five or more letters and the fourth letter is a vowel (a,e,i,o,u), use the first three letters.

(DELay RELay)

You must follow the above rules when entering headers. Creating an arbitrary form, such as POLAR for POLarity, will result in an error.

Introduction To Programming 11