Giga-tronics 8003, Руководство по эксплуатации

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8003 Precision Scalar Analyzer
3-10 Manual 20791, Rev. C, June 2001
3.3.3 Command Execution
A command string is executed when an EOL signal is received (see Section 3.3.3.4). Until an EOL
signal is received the 8003 will parse, check for operational errors and syntax errors and store but not
execute the request as defined by a command string. Any number of context setting VERBS may appear
in an input string. Each time a new VERB is parsed, a new context is established and all specifiers and
modifiers to follow are interpreted for that VERB. The required syntax for each command must be
followed to avoid generating syntax errors. The VERB structures may appear in any order within the
program string.
3.3.3.1 hs Definition
The header separator (hs) mnemonic is defined as zero or more ASCII white space characters between a
command header and accompanying data.
3.3.3.2
ds Definition
The data separator (ds) mnemonic is defined as zero or more ASCII white space characters followed by
an ASCII comma followed by zero or more ASCII white space characters. It can be between any two
items of data. Always see the syntax diagram for the specific command for the proper use of this
separator.
3.3.3.3 us Definition
The unit separator (us) mnemonic is defined as zero or more ASCII white space characters followed by
an ASCII semicolon followed by zero or more ASCII white space characters.
3.3.3.4 EOL Definition
The End Of Line separator (EOL) mnemonic is defined as zero or more ASCII white space characters
followed by zero or one ASCII carriage return character followed by an ASCII line feed character.
Alternatively, the IEEE 488 EOI line may be sent true with the last ASCII character of the last
mnemonic. The command string is executed upon parsing of the EOL command.
3.3.3.5 Case Insensitivity
All of the command mnemonics can be sent in either upper or lowercase. Although the 8003 is
insensitive to case, it is useful to program strings in a mix of upper and lowercase alphas. One suggestion
is to construct VERB and sensor specifier mnemonics in uppercase and all other alpha mnemonics in
lowercase alphas. The reason for this is to make the verbs more visible and hence more readable. Other
programmers reading your ATE code will appreciate this and so will you when you are reviewing code
months after you have written it. All of the examples in this chapter are presented in this fashion.