Use FireWire devices with Mac
You can use FireWire (sometimes called IEEE 1394 or i.LINK) to connect external devices, such as a hard drive or a digital video camera, without needing to restart your computer. A FireWire port provides power, so the connected device usually doesn’t need its own power cord.
Many Mac computers have one or more FireWire 400 ports that transfer data at up to 400 megabits per second (Mbps). Some have a FireWire 800 port that transfers data at up to 800 Mbps.
About connectors
You must use a FireWire cable that has the correct connector for your computer on one end, and the correct connector for the device on the other end. FireWire devices can accept either 4-pin (A), 6-pin (B), or 9-pin (C) connectors. FireWire 400 ports accept 6-pin connectors. FireWire 800 ports accept 9-pin connectors. For example, if you have a device that accepts a 4-pin connector and you want to plug it into your computer’s FireWire 400 port (which accepts a 6-pin connector), you need a 4-pin to 6-pin cable.
About power cords
If your device needs more power than the FireWire port provides, you need to connect the device to a power cord. Check the documentation that came with your device to see if this is necessary.
If you have a portable computer
Using a FireWire device without its own power cord can cause your portable computer’s battery to become depleted faster. If you plan to use such a device for an extended period, it’s a good idea to connect the portable computer’s power adapter.
About connecting multiple devices
You can connect multiple devices to each other and connect the chain of devices to the FireWire port on your computer; however, only one device should get power from the computer. The other devices in the chain should be powered by separate power adapters. Connecting more than one FireWire device that gets power from the port may cause problems. If a problem occurs, shut down the computer, remove the FireWire devices, and restart your computer.