Ieee-488 (gpib) communications, Rs-232, Rs-232 communications – ETS-Lindgren FM5004 Field Monitor (Archived) User Manual
Page 58
Specific IEEE-488 bus commands depend on the software package
you use. To send commands, be sure that the receiver address is set
properly and that the controller also has correctly identified the
receiver as a listening device.
IEEE-488
(GPIB)
C
OMMUNICATIONS
For General Purpose Interface Bus (GPIB) communications, the End or Identify
(EOI) control line may also be used for command termination. When sending
commands to the receiver through the GPIB, terminate the command with
a
system interprets characters following
command.
When an error condition is present at the receiver, the Service Request (SRQ)
signal is asserted. The operator can then perform a serial poll operation. The
receiver error code (in binary) is contained in the lower bits of the serial poll
status byte. If the receiver is addressed as a listener and the GPIB remote line is
asserted, the receiver will switch to remote mode.
RS-232
RS-232
C
OMMUNICATIONS
During initialization, the receiver will test for a properly connected RS-232
interface. For the receiver to recognize an RS-232 device, the Data Carrier
Detect (DCD) line must be asserted. This line is sampled continuously to
determine if the RS-232 connection is broken; therefore, it must remain asserted
for the RS-232 interface to function.
The Clear To Send (CTS) line is also used to gate information from the receiver;
this line must be asserted for information to be transferred from the receiver. The
CTS line can be used as a handshake line to inform the receiver when it is
permissible to send information (there is a five second timeout error built into the
receiver, resulting in an error if the timeout occurs). If the CTS line is de-asserted
in the middle of a transmission, a character in the process of being transmitted
will be completed, and then transmission will halt until the CTS line is
re-asserted.
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Remote Operation
Archived 10/19/10