Measurement Computing Personal488 rev.3.0 For DOS & Windows 3.Xi - Manual (Page 248)

II. SOFTWARE GUIDES - 10. Driver488/W31 10F. Visual Basic
Personal488 User’s Manual, Rev. 3.0 II-233
Accessing from a Windows Program
The structure of a Windows program generally dictates that actions take place in response to messages
such as an operator key press, mouse action, menu selection, etc. This discussion covers the basic
actions needed to control Driver488/W31. How these actions are combined and coordinated in
response to Windows messages is up to the application designer.
The interface between Visual Basic (VB) and Driver488/W31 consists of three pieces:
•
IOTVB10.TXT : A file containing the required external declarations
•
IOTVB10.BAS : A set of interface functions to handle structure conversions
•
IOTEVENT.VBX : An IEEE 488 Event Custom Control
Your application can call all Driver488/W31 functions as
documented in the “Section III: Command References.”
The following functions found in that Section, as shown
in the table, are renamed to avoid conflicts with VB
reserved words:
In order to have access to all the Driver488/W31
functions, you must include the file
IOTVB10.TXT . You
can accomplish this through the Add File item under the
file menu. Type
*.TXT into the selection field to find
the file in your project.
Certain functions provided by Driver488/W31 require
that data structures be passed in a particular format which is not easily generated from a VB
application. Conversion functions are provided in
IOTVB10.BAS , which should be included in the
10F. Visual Basic
Topics
•
Accessing from a Windows Program ....................................... II-232
Opening & Closing the Driver....................................................................II-233
•
Establishing Communications .................................................. II-234
•
Confirming Communications .................................................... II-235
•
IEEE 488 Event Custom Control............................................... II-235
•
Reading Driver Status................................................................. II-238
•
External Device Initialization................................................... II-238
•
Basic Data Acquisition................................................................ II-239
•
Block Data Acquisition ............................................................... II-239
•
Dynamic Data Exchange (DDE) ................................................ II-241
Application ...................................................................................................II-241
Server Links ..................................................................................................II-241
Acquisition Engine ......................................................................................II-243
•
Sample Programs ......................................................................... II-246
Data Acquisition Sample Program ...........................................................II-246
IEEE 488 Event Custom Control Sample Program .................................II-249
Acquisition Engine Sample Program .......................................................II-250
•
Command Summary .................................................................... II-251
Driver488/W31
Command
Visual Basic
Name
Clear ioClear
Close ioClose
Error ioError
Local ioLocal
Output ioOutput
Reset ioReset
Resume ioResume
Stop ioStop
Wait ioWait