ISABR(4)              OpenBSD Programmer's Manual (HP300)             ISABR(4)

NAME
     isabr - Frodo ISA bridge

SYNOPSIS
     isabr0 at frodo?
     isa* at isabr?

DESCRIPTION
     The isabr driver provides access to the ISA slot found in model `t' HP
     9000/4xx workstations.

SEE ALSO
     frodo(4), intro(4), isa(4)

CAVEATS
     Interrupt numbers 0, 1, 2 and 8 are permanently masked on hp300 systems.
     Therefore ISA devices should not configured to use them.

BUGS
     ISA interrupts are not handled correctly.  Some devices cause the
     frodo(4) chip to interrupt, but without any change in its status regis-
     ters; others will correctly interrupt, but frodo(4) will not ack the in-
     terrupt, resulting in an interrupt storm.

     The 4-slot EISA bridge found in model `s' workstations is not supported
     yet.

OpenBSD 4.7                      May 31, 2007                                1
