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GW Instek GDM-8246 Programming Manual User Manual

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GDM-8246 MULTIMETER

PROGRAMMER MANUAL

⎯ 12 ⎯

Table 1 defines the Boolean and other parameter types for the Digital
Multimeter.

Parameter Type

Description

Example

Boolean

Boolean numbers or
values

0, 1

NR1

Integers

0, 1, 18

NR2

Decimal numbers

1.5, 3.141, 8.4

NR3

Floating point numbers

4.5E-1, 8.25E+1

String

Alphanumeric characters

“No error”

Table 1: Parameter Types for Syntax Descriptions

Message Terminator and Message Separator

I. GPIB message terminators

In accordance with IEEE 488.2 standard, any of the following message
terminators are acceptable:

z

LF

^

END

Line feed code (hexadecimal 0A) with END
message

z

LF

Line feed code

z

^

END

Last data byte with END message

These terminators are compatible with most application programs. A
semicolon separates one command from another when the commands
appear on the same line.

GDM-8246 MULTIMETER

PROGRAMMER MANUAL

⎯ 13 ⎯

II. RS232 message terminators

As there is no signal of end message on RS232 bus, therefore, use LF
as message terminator. When a series of commands are sent to the
instrument, it must add a LF to be a judgment for message terminator.
As for query command, the return message of the instrument is also
added a LF for PC to judge message terminator.

Entering Commands

The standards that govern the command set for the Digital Multimeter
allow for a certain amount of flexibility when you enter commands. For
instance, you can abbreviate many commands or combine commands
into one message that you send to the Digital Multimeter. This
flexibility, called friendly listening, saves programming time and makes
the command set easier to remember and use.

Command Characters

The DMM is not sensitive to the case of command characters. You can
enter commands in either uppercase or lowercase.

You can execute any command with white space characters. You must,
however, use at least one space between the parameter and the command
header

Abbreviating Commands

Most commands have a long form and a short form. The listing for
each command in this section shows the abbreviations in uppercase.
For instance, you can enter the query :CONFigure:VOLTage:DC 0
simply as :CONF:VOLT:DC 0

Because the Digital Multimeter hypothesis that a command starts from
the root, you have the option of beginning the initial command header
with a colon (:).