Messages in this thread | | | Date | Sat, 24 Jul 2010 14:18:10 +0200 | From | Stefan Richter <> | Subject | Re: 2.6.35-rc6 to 2.6.32.16: JuJu firewire issues |
| |
Martin Mokrejs wrote: > I tried in the morning to connect the IcyBox to this laptops internal > Ricoh Co Ltd R5C552 IEEE 1394 Controller but had issues to power-up the drive > at all. Not even using USB hub to supply power to it. I connected it to > the ricoh chip via a 6 to 4 pin cable but also tried the not very good > Kouwell 7004 PCMCIA card (which does not supply enough power unless I > buy external, optional power supply of unknown specs and plug it into the > PCMCIA card).
FireWire CardBus cards do not (or more precisely, must not) provide bus power at all, unless if they have a power input port and a fitting PSU is connected to it. If a CardBus card puts power onto the FireWire bus without any extra PSU connected, then this card is miswired and not spec compliant. A FireWire bus power provider is required to be able to deliver 1.5 A current or more, at 8 V or more. That can't be done via CardBus.
4-pin FireWire ports OTOH do not provide bus power of course; they lack the respective pins.
Some FireWire disk enclosures can optionally be powered via USB, but we all know how unreliable USB bus power is. Prefer either a dedicated PSU or regular FireWire bus power. -- Stefan Richter -=====-==-=- -=== ==--- http://arcgraph.de/sr/
| |