Specifications

Chapter 2 31
Outline of Remote Control
Outline of GPIB remote control system
2. Outline of Remote Control
Grammar for massages
The grammar used for sending program messages by GPIB is described below. Program
massage means a massage sent to the measurement equipment by the user through an
external computer for controlling the measurement equipment. A program message
contains one or more commands and the parameters required for them.
Handling of capital/small letters
No differentiation between capital and small letters
Program message terminator
Program messages have to end with any one of these three program message terminators:
<new line>, <^END>, and <new line><^END>. <END> means that EOI becomes the
active level on the GPIB interface when the immediately preceding data byte is sent out.
For example, the OUTPUT command of HTBasic automatically sends the message
terminator after the last data byte.
Parameter
A space (ASCII code 32) is required between a command and the first parameter. When
multiple parameters are sent with one command, the parameters have to be divided by
commas (,).
Message that includes multiple commands
When sending two or more commands in one message, the commands have to be divided
by semi-colons (;). The following is an example of sending the
*CLS command and the
INIT command in the same massage by HTBasic.
OUTPUT 717;"*CLS;:INIT"
Remote mode
The E4991A doesn’t have a remote mode. Therefore, it doesn’t switch to remote mode
even if it receives the relevant GPIB command. Also, there is no local key to release the
remote mode.
When it is necessary to prevent operational error caused by mistaken input through the
front panel or keyboard/mouse of the E4991A under remote control, use one of the
following GPIB commands to lock the input device.
• SYST:KLOC on page 522 (locks front panel)
• SYST:KLOC:KBD on page 522 (locks keyboard)
• SYST:KLOC:MOUS on page 523 (locks mouse)