# BC127 USB to Host

**URL:** <https://forum.sierrawireless.com/t/bc127-usb-to-host/16130>\
**Category:** WiFi and Bluetooth Modules\
**Created:** [April 19, 2019, 4:13pm UTC](https://forum.sierrawireless.com/t/bc127-usb-to-host/16130 "2019-04-19T16:13:29Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![marksoutherland](https://avatars.discourse-cdn.com/v4/letter/m/49beb7/32.png) [@marksoutherland](https://forum.sierrawireless.com/u/marksoutherland)\
**Post date:** [April 19, 2019, 4:13pm UTC](https://forum.sierrawireless.com/t/bc127-usb-to-host/16130/1 "2019-04-19T16:13:29Z")

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Hello,

I would like to be able to use USB to do field FW updates to my company’s BC127 based Bluetooth product.

I see in the documentation that you must do a write and reset to the “USB\_HOST” property over UART and, and then I assume I will be able to interact with the BC127 over USB and do FW updates .

The problem is there is not much else information on the USB\_HOST setting, and I am concerned about reliability as some have reported here they are not able to do USB operations once they enable USB\_HOST.

Is there more information about this feature somewhere? Does this require special CSR drivers or anything like that?

Mark

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**Author:** ![tass2001](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/tass2001/32/3830_2.png) [@tass2001](https://forum.sierrawireless.com/u/tass2001)\
**Post date:** [May 16, 2019, 5:07pm UTC](https://forum.sierrawireless.com/t/bc127-usb-to-host/16130/2 "2019-05-16T17:07:15Z")

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@marksoutherland,

I would avoid using the USB interface for Firmware upgrades, unless you have an MCU speaking to the BC127 over UART. The reason being is that configurations are often reset after a firmware upgrade, so after one upgrade, you’d loose the ability to speak to the BC127 over USB.

I would suggest using an FT232RL as the interface for firmware upgrades.

Thanks,  
-Ted