Spirent DLS 400E3, Руководство по эксплуатации

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DLS 400E3 Operating Manual
Spirent Communications - Page 4-5
7104000537 03/04 -2
4.4 Data Formats
This section applies to both the IEEE 488 and RS-232 interfaces.
The host systemhost system adheres to the IEEE 488.2 principle of Forgiving, Listening and Precise Talk-
ing.
The data formats supported by the host system are:
Talking: a) <NR1> Numeric Response Data - Integer
b) Arbitrary ASCII Response Data
<NR1> is an implicit point representation of an integer (i.e. fixed format).
Arbitrary ASCII Response Data is a generic character string without any delimiting characters. It is usually
used to send data in response to a query, such as with the *IDN? command.
Listening: <NRf> Decimal Numeric Program Data
<NRf> is the Flexible Numeric Representation defined in the IEEE.2 standard which can represent just
about any number.
The host system can accept data in the <NRf> format, which means that numbers can be made of a combina-
tion of digits, signs, decimal points, exponents, multipliers, units and spaces. For example, any of the fol-
lowing is a valid representation for -85.0 dBm: -85dbm, -85.0 dbm, -85, -85.0, -8.5e2. If a unit (i.e. dB, pps,
mv, etc) is appended to a number, that unit must be valid and not abbreviated. Note that the period separates
the decimal part of a number.
4.5 Command Syntax
The host system adheres to the IEEE 488.2 format for command syntax. As with the Data Format, the prin-
ciple is Forgiving Listening and Precise Talking.
Commands may take one of two forms, either a Common Command or a Device Dependent Command. The
format of each is detailed in their respective sections Chapter 4 "COMMON COMMAND SET FOR
REMOTE CONTROL", and Chapter 6 "DEVICE SPECIFIC COMMANDS FOR REMOTE CONTROL").
Each type may be preceded by one or more spaces, and each must have one or more spaces between its mne-
monic and the data associated with it.
Common commands are preceded by the character "*". Device Dependent commands are preceded by a
colon, with a colon separating each level of the command. Commands may be either in upper or lower case.
Multiple commands may be concatenated by separating each command by semi-colons.
The following are some examples:
Table 2-3:RS-232 Example
Action
Comment
transmit "*ESE 60
enable all the error bits (needed only once)
transmit "*IDN?
query the identification message
read the answer
the messages are always terminated with LF
transmit "*ESR?
check if an error occurred
read the answer