53
11.2 Setting up the RS-232 Port for Remote Control
Note:
The RS-232 connection cable should not exceed 5m unless the load capacitance
measured at connection points is less than 2500pF.
Serial parameter values:
9600 baud
8 data bits
stop bit
no parity
Xon/Xoff
EOL (End of Line) character or CR (Carriage Return) or both
To set up remote operation of the calibrator on the Windows Hyper Terminal, connected
to a COM port on the PC as in Figure 3, use the following procedure:
. Start Hyper Terminal
(located in Accessories/Communications of the Windows Start menu)
2. Select New Connection.
3. For Name enter CP 400/420. Select the serial port that the calibrator is connected to.
4. Enter the above information for port settings.
5. Select ASCII setup from File/Properties/Settings and mark these choices:
Echo typed characters locally
Wrap lines that exceed terminal width
6. Select Ok
7. To see if the port works enter *IDN?. This command will return information on the calibrator.
11.3 Changing Between Remote and Local Operation
There are three modes of operation of the calibrator, Local, Remote, and Remote with
Lockout. Local mode is the default mode. Commands may be entered using the keypad
on the calibrator or using a computer. In Remote mode the keypad is disabled, and
commands may only be entered using a computer, but choosing [GO TO LOCAL] from
the menu on the calibrator display will restore keypad operation. In Remote with Lockout,
the keypad can not be used at all. To switch modes proceed as follows:
. To enable Remote mode, type in the serial command REMOTE at the computer terminal.
2. To enable Remote with Lockout, type in “REMOTE LOCKOUT” in either order.
3. To switch back to local operation enter LOCAL at the terminal.
This command also turns off LOCKOUT if it was on. For more information on commands
refer to the Remote Commands section.
11.4 Using Commands
11.4.1 Command types
Refer to the Section .5 on Remote Commands for all available commands.
The calibrator may be controlled using commands and queries. All commands may be
entered using upper or lower case. The commands are divided into the following
categories:
Calibrator Commands
Only the calibrator uses these commands.
For example:
VAL?
asks for the values displayed on the calibrator display.
