What to know about USB 2.0.
There’s a new spec on the immediate horizon for USB, called USB 2.0, and there are some things to know about it right off. USB 2.0 is similar to USB, but with much higher bandwidth (480Mbps vs. 12Mbps for USB version 1.1 – obviously, a HUGE leap; compare this to the current, and also certain to grow, FireWire spec of 400Mbps). USB 2.0 hardware will use the same cables and same connectors so users won’t see any difference in the connection methods. The new USB 2.0 devices will also coexist peacefully with the current USB 1.1 devices on a USB 2.0-enabled system. Also, today’s USB 1.1 connectors and full-speed cables will support the higher speeds of USB 2.0 without any changes.
However, to take advantage of the USB 2.0 hardware, users must also upgrade their current USB 1.1 systems with USB 2.0 compliant PCI cards. Yes, this also means that motherboard-installed USB hardware will not be compliant. Mac motherboards aren’t immediately going to see the hardware upgrade, if their current hardware specifications from hardware introduced at MacWorld this week are any evidence. PC motherboards with built-in USB 2.0 support will not be released until the end of first quarter of 2001, according to Intel.
To support USB 2.0, you need to have a system that has USB 2.0 host controller installed. The new host controllers will appear in two packages: USB PCI cards, and built-in hardware on the motherboard. Before Apple, Intel, VIA or other manufacturers have adapted to the new USB standard, only the USB PCI upgrade package will be available on the market. Although USB 1.1 devices will continue to appear in the marketplace (for low bandwidth products such as keyboards and mouses… err, is that mices?), the plan is that the 2.0 spec will phase out the 1.1 spec completely, as it relates to the USB port hardware.
Operating system support for USB 2.0 seems to be, well… nonexistent at this point. Microsoft and Apple have yet to announce the support for USB 2.0 in their future operating system releases. Despite this, USB 2.0 products are already popping up, and since the new spec is such a dramatic leap from the previous one, users should expect to see some quick implementation.
Some final things you should know: USB 1.1 hubs cannot work with USB 2.0 hardware. Backward compatible with USB 1.1 devices, USB 2.0 repeaters will supersede USB 1.1 hubs. They will be able to talk in three modes: high-speed (480Mbps), full-speed (12Mbps), and low-speed (1.5Mbps). In practice, users will need to connect USB 2.0 hardware on both ends to achieve the “high-speed” mode. On one end, USB 2.0 compliant host controller resides on the host computer to manage the enumeration process and power management. On the other end, USB 2.0 hardware must be connected directly to the root hub or thru a USB 2.0 hub.