Device-Dependent Command Set - Fluke 8845A Manual

Device-Dependent Command Set

Device-dependent commands are the heart of 8842A emulation remote control. They tell
the Meter how and when to make measurements, when to put data on the bus, when to make
service requests, etc. The complete set of device-dependent commands is listed in
Figure 6. The commands may be entered using either upper- or lower-case letters.
Device-dependent commands are device-dependent messages. For the Meter to receive
them, they must be sent over the IEEE-488 bus when the Meter is in remote and has
been addressed as a listener.
The following paragraphs describe the device-dependent commands in alphabetical order.
Special characters (* and ?) are described last.
Bn (Offset Commands)
When the Meter receives the B1 command, the Meter stores the present reading as an
offset for the present function. The B0 command cancels the offset. Only one offset is
allowed at a time.
The offset status (not the offset value) can be read using the G5 command. The Meter
defaults to B0 on both power-up and on any device-clear command (*, DCL, or SDC).
Dn (Display Commands)
The Display commands allow the user to blank the display in the Meter. The D0
command causes the display to operate normally, and is the default on power-up and
upon any device-clear command (*, DCL, or SDC).
The D1 command blanks the display. The D1 command is used for best performance
when high IEEE-488 Interface Data rates are required.
Fn (Function Commands)
The function commands duplicate the front panel function buttons. The Meter defaults to
Fl on power-up and on any device-clear command (*, DCL, or SDC). If F0 is sent to the
Meter, it is internally converted to F1. The function setting can be read using the G0
command.
As with the front panel commands, selecting F6 automatically selects the 2000 mA range
(R5). If the instrument is in range R8, commanding F5 automatically selects the 200 mA
range (R4). If the instrument is in R1 through R6, commanding F5 automatically
selects the 2000 mA range (R5). If the Meter is in a resistance function (F3 or F4) and in
R6, selecting any other function automatically selects R5. If the Meter is in range R8 and
F2 or F3 is commanded, range R1 is selected.
Get Commands
The Get commands "get" information from the Meter for the controller. Each Get
command loads the output buffer with an output string in the format shown in Figure 7.
Status data (the output from Get commands G0, G1, G3, G4, G5, G6, G7 and G8) is
interpreted as shown in Table 30. The Get commands should not be confused with the
interface message GET (Group Execute Trigger).
Remote Operation
FLUKE 8842A Emulation Mode
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