Keithley 7001, Инструкция по эксплуатации

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IEEE-488 Bus Overview
D-8
Typical command sequences
For the various multiline commands, a specific bus se-
quence must take place to properly send the command.
In particular, the correct listen address must be sent to
the instrument before it will respond to addressed
commands. Table D-3 lists a typical bus sequence for
sending the addressed multiline commands. In this in-
stance, the SDC command is being sent to the instru-
ment. UNL is generally sent as part of the sequence to
ensure that no other active listeners are present. Note
that ATN is true for both the listen command and the
SDC command byte itself
Table D-4 gives a typical common command sequence.
In this instance, ATN is true while the instrument is be-
ing addressed, but it is set high while sending the com-
mon command string.
IEEE command groups
Command groups supported by the Model 7001 are
listed in Table D-5. Common commands and SCPI
commands are not included in this list.
Table D-2
Hexadecimal and decimal command codes
Command Hex value
Decimal
value
GTL 01 1
SDC 04 4
GET 08 8
LLO 11 17
DCL 14 20
SPE 18 24
SPD 19 25
LAG 20-3F 32-63
TAG 40-5F 64-95
SCG 60-7F 96-127
UNL 3F 63
UNT 5F 95
Table D-3
Typical addressed command sequence
Data bus
Step Command ATN state ASCII Hex Decimal
1 UNL Set low ? 3F 63
2 LAG* Stays low ’ 27 39
3 SDC Stays low EOT 04 4
4 Returns high
*Assumes primary address = 7.
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