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1560 Thermometer Readout
User's Guide
6.3
64
Command Syntax
The 1560 accepts commands that set parameters, execute functions or respond
with requested data. These commands are in the form of strings of ASCII-en-
coded characters. As far as possible, the 1560 conforms to IEEE-488.2, 1992
and SCPI-1994. One notable exception is that compound commands are not al-
lowed as explained below.
Commands consist of a command header and, if necessary, parameter data. All
commands must be terminated with either a carriage return (ASCII 0D hex or
13 decimal) or newline character (ASCII 0A hex or 10 decimal).
Command headers consist of one or more mnemonics separated by colons (:).
Mnemonics may use letter characters, the underscore character (_), and possi-
bly numeric digits as well. There is no distinguishing between upper and lower
case letters. Mnemonics often have alternate forms. Most mnemonics have a
long form that is more readable and a short form consisting of three or four
characters that is more efficient.
A mnemonic may end with a numeric suffix that specifies one of a set of inde-
pendent function blocks such as input channel data paths. If a numeric suffix is
omitted when a particular block must be specified, a suffix of one is assumed.
Query commands are commands that request data in response. Query com-
mands have a question mark (?) immediately following the command header.
Responses to query commands are generated immediately and placed in the
output buffer. Responses will be lost if not read before the next command is re-
ceived. The input and output buffers can each hold up to 100 characters.
Some commands require parameter data to specify values for one or more pa-
rameters. Parameter data follows the command header with a space (ASCII 20
hex or 32 decimal) between. Multiple parameters are separated by a comma (,).
Parameter data are of one of several types. Numeric data uses ASCII characters
to represent numbers. Numbers may contain a sign ('+' or '-'), decimal point
('.'), and exponent ('E' or 'e') with its sign. If a fractional component is re-
ceived when only an integer is required, the number is rounded to the nearest
integer without any resulting error message. Some commands may accept a
character mnemonic as a number. The mnemonics DEF, MIN, and MAX are
often acceptable for the default, minimum, and maximum value respectively.
Unit suffixes, such as V or OHM, can be appended to numeric parameters and
are accepted without error but ignored.
Boolean parameters have the values of 0 or 1. The mnemonics OFF and ON are
also accepted for 0 and 1 respectively.
Character data are mnemonics that represents one of several possible values.
For instance, temperature units may be specified with CEL for Celsius or FAR
for Fahrenheit.
String data consist of characters enclosed in double quotes. A null string con-
sists of double quotes with no characters enclosed.
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