User manual

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
2000 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 Mod-
el 2000 becomes more than 3/4 full, the instrument issues an X_OFF command. The control
program should respond to this and stop sending characters until the Model 2000 issues the
X_ON, which it will do once its input buffer has dropped below half-full. The Model 2000 rec
-
ognizes X_ON and X_OFF sent from the controller. An X_OFF will cause the Model 2000 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 2000. Data will be lost if transmitted before the receiving device
is ready.
Perform the following steps to set flow control:
1. Access the RS-232 configuration by pressing SHIFT and then RS232. You see: RS
232: ON (assuming you have already selected the RS-232 interface).
Go to the flow control field by using the or key. You see FLOW: <control>.
Access the flow control options by pressing the key. You see the flow control se-
lection blinking.
Use the or key to display the desired flow control (NONE or XonXoFF) and
press ENTER. You will then be prompted to set the terminator. Continue on for infor-
mation about the terminator. You can return to the measurement mode by pressing
EXIT.
The Model 2000 can be configured to terminate each program message that it transmits
to the controller with any combination of <CR> and <LF>. Perform the following steps to set
the terminator:
1. Access the RS-232 configuration by pressing SHIFT and then RS232.
You see: RS 232: ON (assuming you have already selected the RS-232 interface).
Go to the terminator field by using the or key.
You see TX TERM: <terminator>.
Access the terminator options by pressing the key.
You see the terminator selection blinking.
Use the or key to display the desired terminator (LF, CR or LFCR) and press
ENTER. The instrument will return to the measurement mode.
2000-900 (J - Aug 2010) BOOK.fm Page 7 Wednesday, October 12, 2011 12:29 PM