On Tue, May 17, 2011 at 12:16:30PM +0530, Prashant Shah wrote: > Hi, > data16 = 0x0000; > outw(iobase2 + 2, data16); > mb(); udelay(100); You should probably be using outw_p here, it'll wait until the io completes (see outb(2)). But I don't think this will solve your problem. Greetings, Jonathan Neuschäfer