Re: [PARPORT] Re: problems with parallel port IRQ detection

Philip Blundell (Philip.Blundell@pobox.com)
Sun, 01 Feb 1998 12:35:33 +0000

>I have no idea about the parallel port IRQ problem, but the line above
>takes the value returned from parport_pc_read_configb(pb) and extracts the
>3-bit value stored at bits 3,4, and 5:
>
>MSB 7 6 5 4 3 2 1 0 LSB
> ^ ^
> | |
> --------- takes these three bits, and stores the value (range
>will be 0-7) in irq

Thanks. I understood that much already. The problem is that I don't know how
the contents of the "configB" register is defined and I have no idea whether
the bits in question really do constitute a valid magic number to derive an
IRQ from.

p.