Measurement Computing Personal488 rev.3.0 For DOS & Windows 3.Xi - Manual (Page 65)

8D. Getting Started II. SOFTWARE GUIDES - 8. Driver488/DRV
II-50 Personal488 User’s Manual, Rev. 3.0
1. If the external device name is defined on the current hardware interface, then that interface is used
to communicate with that device. The current hardware interface is the one that was opened to
communicate with Driver488/DRV. This would be
IEEE for the first IEEE 488 interface, IEEE2
for the second, etc.
2. If the name is defined on another hardware interface, that other interface is used to communicate
with that device.
3. If the name is defined on more than one other interface (and not on the current interface) then one
of those interfaces is used. The choice of which particular interface is not defined.
4. In order to specify the interface to use, the interface name may be prefixed with a colon to the
device name. For example,
IEEE2:DMM refers to the digital multimeter attached to interface
IEEE2 . If the specified device does not exist on the specified interface, then an error occurs.
Example
Assume there are three IEEE 488 interfaces: IEEE , IEEE2 , and IEEE3 controlling multiple devices:
SCOPE (on IEEE ), DA (on IEEE2 ) and DA (on IEEE3 ). Since there are two external devices, both
named DA , their full name must be used to specify them.
After opening the interfaces with the following command lines:
OPEN “IEEE” AS #1
OPEN “IEEE2" AS #2
OPEN “IEEE3" AS #3
we can communicate with the external devices, according to the four rules above.
PRINT #1,"OUTPUT SCOPE;..." SCOPE on IEEE . See Rule 1
PRINT #3,"OUTPUT SCOPE;..." SCOPE on IEEE (not IEEE2 ). See Rule 2
PRINT #1,"OUTPUT DA;..." DA on IEEE2 or IEEE3 (not specified) . See Rule 3
PRINT #1,"OUTPUT IEEE2:DA;..." DA on IEEE2 . See Rule 4
PRINT #1,"OUTPUT IEEE2:SCOPE;..." ERROR (not IEEE:SCOPE ). See Rule 4
Introduction
Once Driver488/DRV has been installed in your system, it is ready to begin controlling IEEE 488 bus
devices. This Sub-Chapter describes methods of controlling the bus directly from the keyboard. Other
Sub-Chapters in this Chapter develop short programs, in various languages, to control a Keithley
Instruments Model 195 digital multimeter. The techniques used in these programs are quite general,
and apply to the control of most instruments.
It is not necessary to write programs to control IEEE 488 bus devices using Driver488/DRV. Instead,
using the Character Command Language Application Program Interface (CCL API), commands to the
bus may be sent directly from the keyboard, with responses displayed on the screen or sent to a file.
The Keyboard Controller program provides this capability, as do the standard MS-DOS commands.
8D. Getting Started
Topics
•
Introduction..................................................................................... II-49
•
Keyboard Controller Program..................................................... II-50
•
Direct Control from DOS Using CCL ......................................... II-51