When Apple discontinued supporting FireWire on their low-end MacBooks recently, I was disappointed, but not surprised. Apple has been threatening to do this for a while.
I just think this is enormously short-sighted. The need to connect external peripherals does not go away if all you can afford at the moment is a lower-cost notebook.
However, this decision by Apple put me in mind of some information I’ve been sharing as part of my PowerUP seminar tour that I thought I should share with everyone.
Four thoughts on FireWire
1. FireWire does not run at its rated speed
2. FireWire has limits on cable length and connected devices
3. FireWire is hubbed
4. Resetting a FireWire device (power down for 30 seconds)
Rated Speed. When used with a hard disk FireWire doesn’t run at its rated speed, it runs slower. Generally, about 50% of the FireWire rating. This means that you can expect a FireWire 400 drive to transfer data between 20 – 25 MB / second. FireWire 800 drives, generally transfer data between 40 – 50 MB / second.
Cable Limits. When connecting FireWire 400 devices, keep the TOTAL length of cable between all devices to 15 feet or less. Longer total runs are possible with FireWire 800, but a general rule is to keep cable runs as short as possible.
FireWire is Hubbed. Regardless of which computer you use (including a MacPro) or the speed of your FireWire device, the speed of your FireWire devices is determined by the SLOWEST device attached to your computer. This is because all FireWire ports are “hubbed,” meaning they are connected together. I tested this recently by plugging a FireWire 400 hard drive and a FireWire 800 drive into a MacPro at the same time. When both were attached, the FireWire 800 drive read (played back) data at 37 MB / second and wrote (recorded) data at 24 MB/second. When I disconnected the FireWire 400 drive, the speed of the FireWire 800 drive doubled – reading data at 58 MB/second and writing data at 57 MB/second. Cameras and video decks are even slower. If you are getting dropped frame errors, disconnect your camera or deck.
Resetting FireWire. If you have connected a FireWire device, like a hard drive or audio interface, and it doesn’t show up on your system, disconnect the FireWire cable at both ends and power-down the FireWire device. Because FireWire is a powered port, leave the power off for at least 30 seconds to give it time to reset. Then, reconnect everything. If that doesn’t fix the problem, disconnect and power down your FireWire device, then, shutdown your computer. Let everything stay off for at least 30 seconds, then, connect your FireWire device, power-up your FireWire device, then restart your computer. FireWire devices need to be powered up BEFORE starting your computer.
I’ve found these tips very helpful in solving problems and hope you do, as well.
