Thanks for your help. I tried your script. the result is really interesting. the interrupt is still shown as 0 times. I even hacked into the do_IRQ and handle_IRQ_event, let them printk if there is a interrupt number 2 coming in. Still no printk output through klogd logfile. more interesting thing is there is a timer on the multi-port board, which is keeping time-out and keeping the timer interrupt up. Is that possible the board is not enabled to interrupt correctly? really a pain. I just got the driver from the company. don't know what is the start point if I want to really dig into the hardware control of the board. thanks On 6/28/05, Alan Cox <alan@xxxxxxxxxxxxxxxxxxx> wrote: > On Maw, 2005-06-28 at 17:30, rolf liu wrote: > > but the number of interrupts for that driver is always 0, which seems > > not OK. I am wondering if such interrupt is routed to somewhere else? > > I'd expect it to stay zero unless characters were received or events > occurred. Something like > > (echo "Hello world"; cat ) <> /dev/ttywhatever > > ought to cause interrupts > > [That bit of script writes Hello world to the serial port and then > copies anything from it back to it until you hit ^C] > >
