Re: isochronous cycle inconsistent

[Clemens L. <cl...@la...>]

Carl Karsten wrote:
> [  108.048401] firewire_core: created device fw1: GUID 0108000000006351, S800

(As usual, no valid vendor ID ...)

> looped cable to on board port:
>
> [  112.817782] firewire_ohci: isochronous cycle inconsistent

FireWire has isochronous transfers, which rely on a common bus time.
(AV devices and all host controllers are capable of iso transfers.)
To synchronize the time on the bus, one of the iso-capable nodes, the
cycle master, broadcasts its current time every 125 µs.

As long as the two controllers are not connected, each one is cycle
master.  When you connect them, one loses its status as cycle master and
receives its time from the other one.  The resulting change in time is
reported as "isochronous cycle inconsistent".  This is not a bug when
it doesn't happen during normal operation, and the kernel probably
shouldn't report it when it is expected.

> [  143.392293] firewire_core: giving up on config rom for node id ffc1
> [  165.404068] firewire_core: giving up on config rom for node id ffc0

Is your problem that the cards don't eventually see each other?


Regards,
Clemens