Spirent DLS 6700, Operating Manual

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Chapter 4: REMOTE CONTROL
Spirent Communications
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Page 4-5
When the echo is on, the DLS 6700 will echo back all the characters sent to the unit
and display the prompt character “>”.
To query the echo state, send:
:sys:comm:ser:echo?
Note: New units leaving the Access Emulation Division facility will have the echo set
to off.
4.4.3 :SYStem:COMMunicate:SERial:PACE <pace>
Set the receiver and transmitter pace method (flow control) of the serial interface,
where <pace> is any of the following choices:
NONE | CTS | RTS/CTS | XON/XOFF | ALL
For example, to set the pace method to RTS/CTS, send:
:SYS:COMM:SER:PACE RTS/CTS
NOTE
The new pacing must be used immediately for any further serial
communication.
To query the current pacing method send:
:SYS:COMM:SER:PACE?
The command will return the pacing method as a string. For example, if the pacing
method is RTS/CTS, the returned message will be:
RTS/CTS
To simplify the setting of the serial interface, we used a slightly modified SCPI com-
mand set. The SCPI standard requires separate settings for the RTS/CTS flow control
and XOn/XOff pacing, and differentiates between the receive and the transmit sides.
The command set of the DLS 6700 combines the “:RTS” and the “XON” settings into
one “:PACE” command.
Note that the SCPI standard assumes a DTE configuration, whereas the DLS 6700 is
configured as a DCE port (thus not requiring a Null Modem).
4.5 Common Command Set
As specified in the IEEE 488.2 standard, a number of common commands are
required to set up and control the standard functions of remote-controlled devices.
These common commands are as follows:
*CLS
Clear Status Command
Type: Status command
Function: Clears the Event Status Register (ESR). Clearing the Event Status Reg-