7.3.4.1 Setting the Duplex Mode
When the RS-232 duplexmode is set to FULL all commands received by the
1504 from theRS-232 port are echoed back. Setting the mode to HALF dis-
ablesthe echo. The duplex mode can be set remotely using the commands:
DU=F<EOS> sets duplex to full
DU=H<EOS> sets duplex to half
7.3.4.2 Setting the Linefeed Option
When the RS-232 linefeed option is enabled any data transmitted from the
RS-232 portis terminated with a carriage return and a linefeed. Disabling the
linefeed sets the termination tocarriag e return only.The linefeed option can be
set remotelyusing the commands:
LF=ON<EOS> enables linefeed
LF=OF<EOS> disables linefeed
7.3.5 Calibration Commands
The following commands are used in calibrating the instrument.
7.3.5.1 Entering the Password
In order to setthe calibration parameters the password must be issued first. The
followingcommand enables access to the calibration parameters:
*PA=4051<EOS> enables the calibration commands
Calibration parameters can be lockedout again by sending *PA=0 or by cycling
the power.
7.3.5.2 Setting the Menu Lockout
The followingcommands can be used to select the menu lockout options:
*LO=CA<EOS> locks out only the calibration menu
*LO=AL<EOS> locks out all menus
7.3.5.3 Setting the Calibration Coefficients
The instrument calibration coefficients are used to maintain the resistance mea-
surement accuracyof the 1504. These coefficients must not be changed except
by a qualifiedtechnician during the calibration of the 1504. The following
commands can be used toset the instrument calibration coefficients:
*C0=<value><EOS> sets the calibration parameter CAL0
*C1=<value> <EOS> sets the calibration parameter CAL10
*C4=<value><EOS> sets the calibration parameter CAL100
33
7 Digital Communications Interface
Remote Commands