Section Two
Installation and Configuration
©National Instruments Corp.
2-11
GPIB-PC User Manual
Device Map Concepts and Terms
•
Device Name - contains up to seven characters. The rules for
naming devices are the same as DOS rules for naming files,
except that suffixes (
.xxx
) are not allowed. DOS treats
uppercase and lowercase letters identically. The string
"PLOTTER"
is treated the same as the string
"plotter"
. For
this reason, the configuration program maps all lowercase
letters to uppercase.
Device names must not be given the same names as files,
directories, and/or subdirectories. If you name a device
PLTR
and your file system already contains the file
PLTR.DAT
or a
subdirectory
PLTR
, a conflict results.
•
Access Board - all devices on the GPIB require an access board
within the computer. The access board is the GPIB-PC
interface board that provides the hardware link to the computer.
The access board name is of the form
GPIBx
, where
x
is a
digit 0 or 1 representing the appropriate GPIB board number.
The access board name is not alterable.
The string representing a device or board name is the first
variable argument of the function
IBFIND
called at the
beginning of your application program. Refer to Sections Three
and Four for detailed explanations of
IBFIND
.
Lower Level - Device/Board Characteristics
The lower level screens display the currently defined values for
characteristics such as addressing and timeout information of a device
or board. Instructions are available on the screen for selecting a specific
field and for modifying the current settings. The configuration settings
selected for each device and each board are a means of customizing the
communications and other options to be used with that board or device.
The settings for devices specify the characteristics to be used by the
access board for that device when device functions are used.
The settings for boards specify the characteristics to be used with each
board when board functions are used. In the following explanations of
device and board characteristics, notice that some characteristics apply
to both devices and boards and some apply only to boards.