Front Panel Operation
2-117
• To select the control mode; send/receive or talk-only.
• To set the parameters for talk-only.
• To set the parameters for the RS-232 interface (baud
rate, number of data bits and stop bits, and parity.
• To select the data elements to send.
See Section 3 of this manual for details on using the instru-
ment over the RS-232 serial interface.
CONTROL: Use this menu item to select one of the operat-
ing modes for the RS-232 Interface:
• SEND-RECEIVE — This is the normal operating mode
for sending commands to the instrument and for send-
ing data from the instrument to the computer.
• TALK-ONLY — In the talk-only mode, the instrument
ignores commands and simply outputs data, as request-
ed by the printer. When the instrument is in the talk-
only mode, the TALK annunciator turns on. The options
for talk-only are explained as follows:
INTERVAL: This option controls how often readings are
sent (printed). The interval is expressed as 1 out of nnnn
readings.
FORMFEEDS: This option is used to control (enable or dis-
able) page breaks and specify the number of lines per page.
When enabled, a form feed occurs after the specified number
of lines are printed.
BAUD: Use this option to set the baud rate for the RS-232
serial interface. Selections include 19200, 9600, 4800, 2400,
1200, 600 and 300 bits per second.
BITS: Use this option to select the number of data bits (7 or
8) to send over the RS-232 serial interface.
PARITY: Use this option to select parity for the RS-232 se-
rial interface. Selections include none, odd or even parity.
STOP: Use this menu item to select the number of stop bits
to use (1 or 2).
ELEMENTS: This menu item lets you select the data ele-
ments sent. Use one of the range keys to toggle between yes
(y) and no (n).
• RDG — The numeric value of the reading.
• RDG# — The buffer location of the reading. The read-
ing number can be reset to zero from the GENERAL
MENU (see paragraph 2.19.7).
• UNIT — The units of the reading.
• CH# — The channel number the reading was taken on.
• HUM — Relative humidity reading if the Model 6517-
RH is being used. The humidity sensor is enabled from
the A/D CONTROLS item of the GENERAL MENU
(see paragraph 2.19.7).
• ETEMP — The external temperature reading if the
Model 6517-TP is being used. The humidity sensor is
enabled from the A/D CONTROLS item of the GEN-
ERAL MENU (see paragraph 2.19.7).
• TIME — The real-time or relative timestamp for each
reading. Timestamp type is selected from the TIMES-
TAMP item of the GENERAL MENU (see paragraph
2.19.7).
• STATUS — The reading status information (normal
reading, measurement overflow or underflow, relative
reading).
• VSRC — The actual output level of the V-Source.
2.19.3 CAL
The CALIBRATION menu is used to calibrate the Model
6517A.
COMPREHENSIVE, POINT-CALS and CAL-OPT
These procedures for calibration are locked. These proce-
dures require accurate calibration equipment and should
only be performed by qualified personnel. Refer to the Mod-
el 6517 Service Manual for details.
CAL-DATES
Use this menu item to view or change the calibration dates.
Use the VIEW option of the menu to display the last calibra-
tion date and the next calibration date. The DISPLAY-AT-
POWERUP option controls whether the next calibration date
is displayed during the power-up sequence.
The CHANGE option is locked, to enable it requires the
CAL switch to be pressed. The option allows you to change
the calibration date and next calibration date. Refer to the
Model 6517 Service Manual for instructions.
OFFSET-ADJ
Use this menu item to calibrate voltage burden and input off-
set current. After selecting OFFSET-ADJ, you will be
prompted to connect a short to the input triax connector and
then press ENTER. The message “Performing V offset cali-
bration” will be displayed while calibration is in process.
When finished, you will be prompted to remove the short,
cap the triax input connector and then press ENTER. The
message “Performing I Bias calibration” will be displayed
while calibration is in process.
