User's Manual

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If user wants to switch the mode from Modem start-up to USB Disk start-up，the AT command AT+BOOTDEV=0
needs to send to the module. When the module is restart it will be changed to USB Disk start-up mode.
In the Modem mode, the AT command AT+DEVCHG will change the device to be a USB Disk directly.
In USB Disk mode, the USB Disk is a read-only device by default. If user wants to change the module to be read-write,
it needs to switch to modem mode firstly, then use AT commands AT+FILEMODE=0 and AT+DEVCHG. The module
will be read-only again after restart.
Appendix：Mechanical dimensions of U6100
The following are Mechanical dimensions of U6100 bottom view, side view and top view. (Unit: mm)
Bottom View Side View Top View