Spec Will Cut External Drive Power Cords
Lucas123 writes "The Serial ATA International Organization just revealed that it is well along the way to finishing a specification that would remove separate power cords to external SATA drives or optical disk drives, allowing them to draw power from the host system. The resulting new cable, being called Power Over eSATA, will be compatible with the existing eSATA connector and support the current maximum interface transfer rate of 3Gb/s. The SATA organization expects the new cables to be released later this year to drive makers."
I think the advantage is supposed to be cost and speed. eSATA is faster than USB and Firewire (I think, dunno about the latest Firewire) and requires absolutely _no_ on board logic to work. With this new spec an external eSATA case is literally a metal box with a hole in it, maybe a passthrough connector if they're feeling swanky. They don't even need the transformer anymore. That makes it cheaper than USB and especially firewire.
I read the internet for the articles.
FireWire is a fairly general-purpose specification, designed so that devices that require a fixed (and quite large) amount of bandwidth can be guaranteed it, and designed with device-to-device communication in mind. Its maximum bandwidth is 400Mbps (unless you count FW800, which I will as soon as I see a device that supports it).
SATA is a storage-device-oriented specification, designed pretty much so that drives can pump data over it as fast as they can read it, with a centralized paradigm and a much higher peak bandwidth at 1.5Gbps (or 3Gbps, but see the note about FW800 above).
Using USB for storage devices is perverted and wrong; it's synchronous, so your practical bandwidth is limited by the length of your cable and the response time of the nodes at either side. On the other hand, a design like that is pretty great for things like user input devices, which is one reason nobody ever talks about making FireWire mice.
So, in summary, SATA is more suitable for disks than FireWire, and USB is dog-slow. Any questions?
-:sigma.SB
WARN
THERE IS ANOTHER SYSTEM