mikropascal pic pro example usb
Hi pixel,
USB is designed to be compatible all its version. Even version 2 is compatible with version 1 and 1.1. All product designed with 1 will work 1.1 and 2. Phrase "USB 2.0 compatible" is just marketing gimik.
Actully, USB when designed by Intel (since Intel dosen't have any serial protocol standard in its name while its competetors viz Motorolla has SPI, National has Microwire and Philips has I2C) it was supposed to fastest of all serial standard. But when Firewire promoted by Apple proves running at 600 to 800 MHz, Intel started to experiment with USB again and found that it too can goes upto 400 MHz. Hence they then created version 2 named High-speed mode. With this, now officially USB has three speed: Low speed 1-2 MHz, Full spead 12 MHz and High speed 380 MHz.
All product intially start with either USB Full speed or Low speed. Then when Host (PC) allow, depending its bandwidth and CPU applications load, switch to High speed 380 MHz.
I hope this will clarify more.
Regards,