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Chapter 4  Remote Interface Reference
An Introduction to the SCPI Language
4
SCPI Parameter Types 
The SCPI language defines several different data formats to be used in 
program messages and response messages. 
Numeric Parameters  Commands that require numeric parameters 
will accept all commonly used decimal representations of numbers 
including optional signs, decimal points, and scientific notation. Special 
values for numeric parameters like MINimum, MAXimum, and DEFault 
are also accepted. You can also send engineering unit suffixes with 
numeric parameters (e.g., Mhz or Khz). If only specific numeric values 
are accepted, the function generator will automatically round the input 
numeric parameters. The following command uses a numeric parameter:
FREQuency {<frequency>|MINimum|MAXimum}
Discrete Parameters  Discrete parameters are used to program 
settings that have a limited number of values (like BUS or IMMediate). 
They have a short form and a long form just like command keywords. 
You can mix upper- and lower-case letters. Query responses will always 
return the short form in all upper-case letters. The following command 
uses discrete parameters: 
SWEep:SPACing {LINear|LOGarithmic} 
Boolean Parameters Boolean parameters represent a single binary 
condition that is either true or false. For a false condition, the function 
generator will accept “OFF” or “0”. For a true condition, the function 
generator will accept “ON” or “1”. When you query a boolean setting, 
the instrument will always return “0” or “1”. The following command 
uses a boolean parameter: 
AM:STATe {OFF|ON} 
String Parameters String parameters can contain virtually any set of 
ASCII characters. A string must begin and end with matching quotes; 
either with a single quote or a double quote. You can include the quote 
delimiter as part of the string by typing it twice without any characters 
in between. The following command uses a string parameter:
DISPlay:TEXT <quoted string> 
33210A users guide.book  Page 269  Wednesday, July 16, 2008  11:16 AM