COM3 I/O port

On Aug 19, 8:21*pm, fenwayfool <peterson.russ...@gmail.com> wrote:[color=blue]
> I am trying to get COM3 working running vxworks 6.x on an Intel
> processor.
>
> The code base I have uses the vxBus method for configuring the COM
> devices. *The ICH is an ICH7 connected to a winbond superIO chip.
>
> I am able to configure the superIO chip (logical device 6 is UART C)
> and read back the correct values. *I set UART C to use I/O port 0x3e8
> which I believe is standard for COM3.
>
> The problem is, while I can program and enable UART C on the superIO
> chip, I am unable to access the device using I/O address 0x3e8. *Seems
> like the I/O decode for that address is not active.
>
> I took a close look at the ICH7 and see that "COMA" and "COMB" are
> enabled and set to the correct I/O ports but there is no specific bit
> for COMC? *I tried playing with the generic I/O decode registers on
> the LPC bridge but that seems to have no effect.
>
> Anyone have some knowledge on this somewhat esoteric issue?
>
> Thanks.[/color]

I forgot to add that I have indeed updated hwconf.c. Seems the probe
call fails when it tries to see if the COM3 device is actually there.
I believe it is simply writing a value to the interrupt register for
superIO logical device 6 and reading it back... but that fails. All
we read for I/O port 0x3e8 is 0xff.