Model 6487 Reference Manual
Remote Operation
9-17
Make sure that the programming terminal that you are connecting to the Model 6487 can
support the baud rate you selected. Both the Model 6487 and the other device must be con-
figured for the same baud rate.
Data and stop bits
The RS-232 can be set to transfer data using seven or eight data bits and one stop bit.
Parity
Parity for the RS-232 interface can be set to none, even, or odd.
Terminator
The Model 6487 can be configured to terminate each program message that it transmits to
the controller with any of the following combinations of <CR> and <LF>:
•
LF
line feed
•
CR
carriage return
•
LFCR
line feed, carriage return
•
CRLF
carriage return, line feed
Flow control (signal handshaking)
Signal handshaking between the controller and the instrument allows the two devices to
communicate to each other regarding being ready or not ready to receive data. The
Model 6487 does not support hardware handshaking (flow control).
Software flow control is in the form of X_ON and X_OFF characters and is enabled when
XonXoFF is selected from the RS232 FLOW menu. When the input queue of the
Model 6487 becomes more than
i
full, the instrument issues an X_OFF command. The
control program should respond to this and stop sending characters until the Model 6487
issues the X_ON, which it will do once its input buffer has dropped below full. The
Model 6487 recognizes X_ON and X_OFF sent from the controller. An X_OFF will cause
the Model 6487 to stop outputting characters until it sees an X_ON. Incoming commands
are processed after the <CR> character is received from the controller.
If NONE is the selected flow control, then there will be no signal handshaking between the
controller and the Model 6487. Data will be lost if transmitted before the receiving device
is ready.