[RndTbl] parallel port

Trevor Cordes trevor at tecnopolis.ca
Mon Jan 12 01:24:32 CST 2015

On 2015-01-10 Adam Thompson wrote:
> My point was this:
> "By default IRQs are not used even if they _can_ be probed."
> What happens if you explicitly specify the (detected) IRQ on the
> kernel command line or modprobe options?  Same thing?

Yup.  Unless you mean setting some other value.  7 is what is detected
(seems to be a standard as most examples/outputs show it).  I do/did
specify it manually (and io addrs et al) during my tests, no change.  I
even tried some off the wall permutations/choices and only succeeded in
getting nothing to print until setting it back to probed values.

I have a sneaking suspicion that this mobo has a f/w bug (and it's too
late to report it to Intel), or kernel doesn't like my IO chip.  Though
the latter case is more hopeful, it also sucks because the interest in
fixing a parallel port issue by kernel devs will be about negative 5.

I don't mind living with the problem (when do I need to print fast?
and who cares about 100% cpu for 30s once in a blue moon), or just using
a USB->serial doohicky (haven't tried yet), but my first inclination is
always bug report + attempt to fix.  It gives a chance for me to
receive a great round of indifference.

(Further: yes, I'm using the latest mobo BIOS, no they don't mention
parport problems in the notes.  The BIOS gives an option for print mode
only (output only, bidir, EPP, ECP), and (unlike other boards) no
options for tweaking the ioaddr, irq, dma, etc.  This BIOS also does
not give a "PnP OS" option, which may have helped (by toggling), but
I'm pretty sure that choice is hardcoded to NO in this example.)

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