Spirent DLS 6700, Руководство по эксплуатации

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DLS 6700 Operating Manual
Page 4-2 7104000557 Spirent Communications
itself (inside the quotes), so that the carriage return can be interpreted as a second
command, and be simply discarded by the DLS 6700. For example:
PRINT #1, “:set:channel:line 1”+CHR$(10); Preferred solution
OR
PRINT #1, “:set:channel:line 1;” Alternate solution
4.1.2 Example using the RS–232 Interface
To change the length of the line to 4000 ft, do the following:
1) transmit “:SET:CHAN:LINE 1, 4000 ft”
2) check that the REMOTE LED is still green; if it turns red, see Section Chapter 5
"TROUBLESHOOTING".
To send and receive messages with error checking follow these steps:
1) set all relevant enable bits (only done once)
2) send the message
3) read the answer until you receive LF (decimal 10, hex 0A)
4) check if an error occurred with the command *ESR?
For example, to get the identification message with the RS–232 interface, do the fol-
lowing:
1) transmit “*ESE 60” enable all the error bits (needed only once)
2) transmit “*IDN?” query the identification message
3) read the answer the messages are always terminated with LF
4) transmit “*ESR?” check if an error occurred
5) read the answer. If not 0, an error has occurred. See Event Status
Register (ESR) Section for description of the error(s)
4.2 Data Formats
The DLS 6700 adheres to the IEEE 488.2 principle of Forgiving Listening and Precise
Talking.
The data formats supported by the DLS 6700 are:
Talking: a) <NR1> Numeric Response Data – Integer
b) Arbitrary ASCII Response Data
<NR1> is an implicit point representation of an integer.
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 (see Section Section 4.5 "Common Command Set").
Listening: <NRf> Decimal Numeric Program Data
<NRf> is the Flexible Numeric Representation defined in the IEEE 488.2 standard
which can represent just about any number.
The DLS 6700 can accept data in the <NRf> format, which means that numbers can
be made of a combination of digits, signs, decimal point, exponent, multiplier, unit
and spaces. For example, any of the following is a valid representation for 4000 feet:
4kft, 4.0kft, 4000, .04e2k, 0.4 e4 ft, +4000. If a unit (i.e. ft, m, bps, 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.