"scsi bus continuously busy"

[Phil Blundell]

On Sat, May 02, 2020 at 10:22:02AM -0700, Alan Perry via cctalk wrote:
> >sc0 at vme24d16 200000 vec 0x40
> >sd0 at sc0 slave 0
> >si0:  sc_cmd:  scsi bus continuously busy
> >sc0:  resetting scsi bus
> >sd1 at sc0 slave 1

Not that I know these particular devices, but is it at all possible one
of the cables is in backwards?  That sounds like the kind of behaviour
you get with 50-pin SCSI if an IDC connector is upside down.

But otherwise, this message presumably means the host controller is
sensing BSY# asserted when it didn't expect it.  So the first order of
business would be to find out whether BSY# on the bus is genuinely
low.  If not, it must be a controller fault.  If yes, disconnect the
devices one at a time and see if the problem goes away.  If it's still
stuck low with no devices attached, the issue is either in the
controller or termination.

p.