Rohde & Schwarz R&S UPP, Руководство пользователя

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Remote Control - Fundamentals
R&S
®
UPP
657 User Manual 1411.1055.32 ─ 10
Figure 6-2: Device model for remote control via IEC/IEEE bus or TCP/IP network
6.6.1 Input Unit
The input unit receives commands in the form of characters from the IEC/IEEE bus or
Ethernet and collects them in the input buffer. The input unit sends a message to the
command recognition as soon as it detects an end character according to IEEE 488.2
(new line = ASCII code 10 decimal or EOI line becomes active), the interface message
DCL or a full input buffer. If the input buffer is full, the IEC/IEEE bus or Ethernet trans-
fer is halted and the data received until then are processed. Then the IEC/IEEE bus or
Ethernet transfer is continued. If the buffer is not yet full when the end character is
received however, the input unit can receive the next command while the previous
command is parsed and executed. Reception of a DCL clears the input buffer and
immediately triggers a message to the parser.
6.6.2 Parser Analyzes
The parser analyzes the data received from the input unit. Data are processed in the
sequence in which they were received. Only a DCL is given priority; a GET (Group
Execute Trigger) for example is not processed until after the previously received com-
mands. Every command detected as correct is immediately forwarded to the database
and executed.
Device Model and Command Processing