dvgrab: "Error: no camera exists"

[peter_b]

[PROBLEM]
On a smoothly running DV-capture setup on Ubuntu 12.04 (precise) setup, which has already served in ingesting hundreds of DV-tapes without problems, we've changed the replayer (Sony HVR-M25E) to the follow-up model (Sony HVR-M35E).

Now dvgrab complains that it can't find the new replayer:

Error: no camera exists

Kernel modules for firewire are loaded ($ lsmod | grep fire):

Code: Select all

firewire_ohci          41000  0 
firewire_core          63600  1 firewire_ohci
crc_itu_t              12707  1 firewire_core

Kernel log says the following, when connecting the replayer ($ dmesg | tail) :

[ 589.974319] firewire_core: IRM has link off, making local node (ffc0) root.
[ 589.974324] firewire_core: phy config: card 0, new root=ffc0, gap_count=5
[ 592.315564] firewire_core: phy config: card 0, new root=ffc1, gap_count=5
[ 593.472595] firewire_core: giving up on config rom for node id ffc0

[SOLUTION]
Seems to have been bad cable
After rebooting, re-plugging, re-connecting the replayer (different cable, different fw-adapter port), it suddenly worked.

[ 363.814667] firewire_core: phy config: card 0, new root=ffc1, gap_count=5
[ 366.140003] firewire_core: phy config: card 0, new root=ffc1, gap_count=5
[ 367.320339] firewire_core: created device fw1: GUID 0800460103f215cd, S100, 1 config RO

Interesting... Now 2 firewire devices show up:

Code: Select all

crw-------  1 root root  249, 0 Jän 29 15:14 /dev/fw0
crw-rw----+ 1 root video 249, 1 Jän 29 15:19 /dev/fw1

Since firewire can be daisy-chained, I suspect "/dev/fw0" to be the controller, and "/dev/fw1" to actually be the first device attached (currently only one). dvgrab, dvcont, and friends now worked again happily!


Additional information:
1) Something else I found good to know is: /sys/bus/firewire/devices/fwX
This can be used to gather some information about ieee1394-devices your kernel sees - and if it seems connected at all

2) The replayer will not show up if attached, but in standby - even if the lights on the deck give the impression that it has power. It must be turned on in order for the /dev/fw1 device to appear.


Links:

• New ieee1394 Kernel Module "Juju"