Omega OMB-PER-488/W95, User Manual

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40 Personal488/MM (with GP488B/MM) Personal488 User's Manual For Windows95 and Windows NT
Updating the Existing Hardware Drivers
Updating the GP488B/MM Interface Hardware Drivers
1. Insert the disk titled "Driver488 Driver Disk, 1 of 1" into the floppy disk drive.
2. Open the
Control Panel
window from the
Start > Settings
menu, click on the
System
icon, and
select the
Device Manager
tab. Look for a device type named "IEEE488.2 Controllers".
3. Highlight the device you want to update under "IEEE488.2 Controllers".
4. Click on the
Properties
button. Click on the
Driver
tab.
5. Highlight the driver file named "C:\Windows\System\___488.vxd". (For example,
"…\vpci488.vxd".)
6. Click on the
Change Driver
button.
7. Select the model that you are updating. Click
OK
.
Note:
DO NOT select the
Have Disk...
button.
8. Windows will return you to the
Driver
tab. Click
OK
. The hardware drivers will now be updated
from the Driver Disk.
9. Windows will prompt you if you wish to restart the system. Select
Yes
. Otherwise the hardware
will continue to use the outdated drivers until the next time the system is restarted.
Configuring Other Hardware Settings
Configuring the GP488B/MM Interface Internal Clock
The IEEE 488 bus interface circuitry requires a master clock. This clock is normally connected to an
on-board 8 MHz clock oscillator. However, some compatible IEEE 488 interface boards connect this
clock to the PC’s own clock signal. Using the PC clock to drive the IEEE 488 bus clock is not
recommended because the PC clock frequency depends on the model of computer. A standard PC has
a 4.77 MHz clock, while an AT might have a 6 MHz or 8 MHz clock. Other manufacturers’ computers
may have almost any frequency clock. If you are using a software package designed for an interface
board (that derived its clock from the PC clock) and you need to do the same to use GP488B/MM with
that particular software, the clock source can be changed. However, the clock frequency must never be
greater than 8 MHz, and clock frequency must be correctly entered in the Driver488 software.