The Huawei E220 is a Huawei HSDPA access device ( 'modem' ) manufactured by Huawei and notable for using the USB interface (USB modem).
Features :
The device contains not only the cellular antenna but also about 22MB (10 MB on older versions) of storage memory accessible to the operating system as a USB mass storage device[7] formatted with CDFS, thus emulating a CD-ROM drive. In this memory, E220 devices supplied by mobile operators may contain 3G dialer software written by the operator, while Huawei-branded devices contain Huawei's original firmware. Huawei's firmware and updates for it are also available for flashing from Huawei's website, or the newest firmware 7.2 Mbit/s from Mobile Broadband Rocks (in reality 'flashing' this device means writing a firmware image to its internal flash memory). Flashing the firmware of this device doesn't change the memory used for their operator's software, therefore connection settings (such as APN) will be retained. The software loaded on the device may start automatically through Windows's autostart facility, which can be bypassed by pressing the Shift key while inserting the USB cable of E220.
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