Talk:FireWire
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Why do lots of PC makers mark the port as 1394 rather than FireWire? Edward 13:51, 28 Jun 2004 (UTC)
- Apple had a trademark on "FireWire" so they had to use 1394 (the IEEE numerical designation), until Apple donated the trademark to IEEE in order to make it the standard name. Philwelch 19:47, 29 Jun 2004 (UTC)
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about language
One thing that writers in the encyclopedia and elsewhere in the real world ought to understand is their audience - Writing or speaking is a form of communication... and communication, by definition, has to use words which are in the vocabulary of the person who is reading... I came here today looking for information on firewire - I've used computers for some time - but I find I'm lost in the maze of techno words... I would also suggest at least one image of a firewire cable - with the plug end of it prominently featured. People think visually - and that one image would give them a springboard with which to approach the topic.
about location
"All digital televisions and set-top-boxes that support recording the standard MPEG-2 streams also have FireWire ports."
Perhaps it should be added which country this is true for (USA?). There are several products available in the UK that record MPEG-2 (DVB-T and DVB-S) that don't have FireWire ports. Quig 21:07, 30 Sep 2004 (UTC)
Firewire 400 speeds
"FireWire 400 can transfer data between devices at 100, 200, or 400 Mbit/s data rates (actually 98.304, 196.608, or 393.216 Mbit/s, but commonly referred to as S100, S200, and S400)."
Could someone elaborate on this? I can upload files to my iPod mini at 27 Mbit/s, which seems to suggest that FireWire 400 can transfer data between devices at any speeds between 0 ~ 400 Mbit/s. What is the meaning of 100 and 200 Mbit/s speeds? --Tokek 15:40, 6 Mar 2005 (UTC)
Firewire 800
IIRC, loops of devices are allowed with Firewire 800.
Perhaps "Firewire 800" should be in its own little sub-section. It has a different connector, different allowable topology, different allowable medium ... basically it's different from (normal) Firewire in a number of ways. Also, it's not nearly as common. If I was coming here for information about Firewire, I'd find it easier if I saw all the Firewire 800 stuff in its own section, could tell that that's not what I'm interested in, and could ignore that section.
pc to pc connect
may i connect the pc to pc with the use of IEEE1394 as UTP connect
how it's possiable
what the pin connections
and is it work on 400 or 800 mbps speed
i have my network with E-net 100 mbps speed and its very slow
tell me scpl_jdp@yahoo.com
--
Answer : yes. Just plugin a normal FireWire cable into both PCs. Under Windows XP it works automagically ;-) The speed is 400 Mbit/s (unless you have FW-800, then its faster)
RDMA
Anyone have an idea if Firewire is a reasonable approach to software RDMA, as compared with ethernet? It looks like it could have lower latency than ethernet, from bypassing the TCP stack, yet it's commodity hardware much cheaper than (e.g.) Infiniband. Is there a complex transaction setup? How does it deal with multiple nodes on the same bus--collision detection or what? Phr 07:23, 8 Jan 2005 (UTC)
- I can't answer your question directly or authoritatively, here's what the FreeBSD firewire(4) manual page says:
Up to 63 devices, including the host itself, can be attached to a
firewire bus. The root node is dynamically assigned with PHY device
function. Also, the other firewire bus specific parameters, e.g., node
ID, cycle master, isochronous resource manager and bus manager, are
dynamically assigned, after bus reset is initiated. On firewire bus,
every device is identified with EUI 64 address.
- ...so it seems to be some sort of centralized scheduling model. From looking at the driver, there appear to be hardware limitations on the number of simultaneous isochronous transfers that may be set up, but the driver is very difficult to understand without having the standard to compare. 18.26.0.18 23:06, 29 Jan 2005 (UTC)
It sounds like a very good use of FireWire; but you'd have to do some timing
measurements to be sure. (I don't know what advantage ethernet would have
over FireWire in this case? Does Ethernet already support RDMA?)
Devices on the FireWire bus arbitrate for access to it. Each packet sent is repeated
to all nodes, but ignored by those to which it is not addressed. You can do RDMA
(as described in the article) with asynchronous transfers, similarly to a FireWire hard
drive--these types of transfers are acknowledged.
Configuration would be done by creating entries in each machine's configuration ROM.
The configuration ROM (not really a ROM, since it can be updated at any time) is a
reserved section of FireWire address space on each connected device used to advertise
it's services to other devices on the bus. On Mac OS X, you can do this from an application
without writing any kernel code.
Bus Power values
Can someone please look up what power is supplied on the FireWire bus ? How much can a FW device take, without violating the standard ? What voltage? What current ?
I tried myself to find this information, but failed.
Thanks, xerces8@butn.net (please notify me when this is added)
Throwing down the gauntlet
It appears the PC World has a better written article than we do! See http://www.pcworld.com/howto/article/0,aid,14371,00.asp if you don't believe me. What do people think? - Ta bu shi da yu 08:02, 8 Jun 2005 (UTC)