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Hello, I have problem with USB device. I'm loading prodram to my AT91SAM7SE-EK (for example HID MOUSE PROJECT) and it wasn't work. Computer recognize the device but it can't instal. I use Windows Vista, but try on XP and Windows 7 and always was the same. Please help me.
> Could you explain me why with USB HUB it's works?
Interrupt and isoc endpoints reserve required bandwidth at enumeration. If bus bandwidth doesn't remain for new device of these endpoints, enumeration fails. Windows show code 10 error. It was your case.
Nowadays, PC USB ports are high-speed capable. These ports connect to two USB host controllers (HCs), high-speed (HS) HC and low-/full-speed (FS/LS) one. Depending on the device speed, the ports select one of the HCs. As the Atmel chip is a FS device, it is connected to FS/LS HC, when the board is directly plugged in to the PC USB port.
The bandwidth of the FS/LS HC of your PC saturates with the Atmel board. Maybe it is shared by too many devices, mouse/keyboard, audio device, etc.
When a HS (USB2.0) hub is inserted between the Atmel board and the PC port, the hub translates FS transactions into HS ones. Now, the board is connected to HS HC on the PC, instead of FS/LS one. In this reason, the board is successfully enumerated over the hub.
Tsuneo