Input Syntax - Fluke 8845A Manual

1. Implements the default settings Fl, R0, S0, T0, D0, B0, Y0, W0.
2. Clears the error status register (equivalent to X0).
3. Zeros the SRQ mask, prohibiting service requests (equivalent to N0 P1).
4. Zeros the numeric entry register (equivalent to N0).
5. Zeros the serial poll register.
6. Sets the SRQ line false.
The asterisk command is executed in its proper turn in a string, just like any other
command, without affecting the contents of the input buffer. All commands which
precede the asterisk command are performed.
The asterisk command is useful to ensure that the Meter is initialized to the same state
each time a program is run. By contrast, the similar interface messages DCL (Device
Clear) and SDC (Selected Device Clear) cause the entire input buffer to be cleared
immediately.
DCL, SDC, and the asterisk command are all considered to be device-clear commands
because the results are so similar; however, DCL and SDC are not identical to the asterisk
command described here.
? (Single-Trigger Command)
The Single-Trigger command (?) causes the Meter to take a reading and place the result
into the output buffer. To accept this command, the Meter must be in external trigger
mode (selected by the T1, T2, T3, or T4 command).
The Single-Trigger command is one of five ways to trigger a reading. Of these, only
the Single-Trigger command (?) and the Group Execute Trigger command (GET) are
loaded into the input buffer.

Input Syntax

The following paragraphs describe how to construct groups of commands for the 8842A
command emulation. A few definitions are presented first, followed by a description of
how the Meter processes input commands. Guidelines are then summarized in four
syntax rules.
Definitions
•
Output commands: Commands which load data into the output buffer. The output
commands are: the Get commands (G0 through G8); the Single-Trigger
Command (?); the Continuous Trigger command (T0); and Group Execute Trigger
(GET), not to be confused with the Get commands.
•
Input terminator: An ASCII control code sent by the controller which tells the Meter
to execute all device-dependent commands since the previous terminator.
Terminators are CR (Carriage Return), LF (Line Feed), EOI (End Or Identify), and
GET (Group Execute Trigger).
•
Input command string: One or more device-dependent commands followed by a
terminator
Input Processing
When the Meter receives commands from the bus, it stores them in a 350-character input
buffer as a continuous string of characters. Commands in the input buffer are not
executed or checked for syntax until an input terminator is received or the input buffer
Remote Operation
FLUKE 8842A Emulation Mode
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