Measurement Computing Personal488 rev.3.0 For DOS & Windows 3.Xi - Manual (Page 80)

II. SOFTWARE GUIDES - 8. Driver488/DRV 8G. QuickBASIC
Personal488 User’s Manual, Rev. 3.0 II-65
SUBROUTINE OpenIeee
Open(1,File=’\dev\ieeeout’,Status=’OLD’,
1 Access=’SEQUENTIAL’)
Open(2,File=’\dev\ieeein’,Status=’OLD’,
1 Access=’SEQUENTIAL’,Form=’BINARY’)
END
SUBROUTINE FlushIeee
Rewind 1
Rewind 2
END
FUNCTION StrLen(String,MaxLen)
Character String*127
StrLen=MaxLen-1
DO 10 i=1,MaxLen-2
If (String(i:i) .eq. CHAR(13) .and.
1 String(i+1:i+1) .eq. CHAR(10)) then
StrLen=i-1
Goto 20
EndIf
10 Continue
20 Continue
END
Use of the Character Command Language
Several versions of Microsoft QuickBASIC are currently popular: 2.0, 3.0, 4.0, and 4.5. While they
vary considerably in their user interface and performance, they are virtually identical when it comes to
controlling Driver488/DRV. Two demonstration programs are included for QuickBASIC:
195DEMO.BAS and 195DEMO4.BAS . 195DEMO.BAS is compatible with versions 2.0 and higher of
QuickBASIC, while 195DEMO4.BAS requires version 4.0 or version 4.5. These examples can be found
on the Driver488/DRV disk in the \QB directory.
To execute the demo program, start QuickBASIC with the QB /L command. The /L parameter tells
QuickBASIC to load the default library containing the ABSOLUTE subroutine. This /L parameter is not
needed in version 4.0 using 195DEMO4.BAS . Also, in earlier versions of QuickBASIC, such as 2.0, the
EVENT TRAPPING and CHECKING BETWEEN STATEMENTS compiler options must be turned on for the
program to compile and execute correctly.
Initialization of the System
Any program using Driver488/DRV must first establish communications with the Driver488/DRV
software driver. In BASIC and most other languages this is accomplished using an
OPEN statement.
Communication both to and from Driver488/DRV is required. In BASIC, this means that two files
8G. QuickBASIC
Topics
•
Use of the Character Command Language............................... II-64
•
Initialization of the System.......................................................... II-64
•
Configuration of the 195 DMM .................................................... II-66
•
Taking Readings............................................................................. II-66
•
Buffer Transfers ............................................................................. II-67
•
BASIC VARPTR & SADDR ........................................................... II-68
•
Interrupt Handling ........................................................................ II-68
•
Sample Program ............................................................................. II-70