Port read access problems under WinNT

[macke]

I'm using LabWindows/CVI for accessing a self made ISA-bus interface card. Each port read access fails, though the correct data is visible at the ISA-bus. Each port read (using inp()) returns 0xFE.

- operating system is WinNT 4.0
- the low-level support driver is loaded at startup
- write port access (using outp()) works

Can somebody help me in this topic?

Thanks,
Markus

[Sastry V.]

Hi Markus,
I collected some information on this problem. Please see if it works :

1. Try running the example program in this link and see if it works fine.

http://ae.natinst.com/devzone/explprog.nsf/41ee12ddba6c766a8625684700691463/4066173b8d98118a86256a79...

http://ae.natinst.com/devzone/explprog.nsf/41ee12ddba6c766a8625684700691463/78e7f3ac0de597fd86256aa2...

2. Please take a look at this discussions forum issue which might help you :


ref = "http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RNAME=ViewQuestion&HOID=50650000000...