Rohde & Schwarz CMW500 Series, User Manual

Page: 164 / 291

Remote Control
R&S
®
CMW500
164 User Manual 1173.9463.02 ─ 02
6.5 Command Processing
The block diagram below shows how remote commands are serviced in the instrument.
The individual components work independently and simultaneously. They communicate
with each other by means of so-called "messages".
The instrument model consists of the following components.
● Input Unit ...............................................................................................................164
● Command Recognition ..........................................................................................165
● Data Base and Instrument Hardware ....................................................................165
● Status Reporting System ......................................................................................166
● Output Unit ............................................................................................................166
6.5.1 Input Unit
The input unit receives commands character by character from the controller and collects
them in the input buffer. The input unit sends a message to the command recognition as
soon as the input buffer is full or as soon as it receives a delimiter,
<PROGRAM MESSAGE
TERMINATOR>
, as defined in IEEE 488.2, or the interface message
DCL
.
If the input buffer is full, the message data traffic is stopped and the data received up to
then is processed. Subsequently the traffic is continued. If, however, the buffer is not yet
full when receiving the delimiter, the input unit can already receive the next command
Command Processing