# OTP/Bootloader Source

**URL:** <https://forums.sifive.com/t/otp-bootloader-source/214>\
**Category:** HiFive1 Rev B\
**Created:** [December 28, 2016, 6:53pm UTC](https://forums.sifive.com/t/otp-bootloader-source/214 "2016-12-28T18:53:19Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![donb](https://sea2.discourse-cdn.com/flex020/user_avatar/forums.sifive.com/donb/32/41_2.png) [@donb](https://forums.sifive.com/u/donb)\
**Post date:** [December 28, 2016, 6:53pm UTC](https://forums.sifive.com/t/otp-bootloader-source/214/1 "2016-12-28T18:53:19Z")

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Hi Team,

Congrats on a strong release for the first set of boards!

Will the OTP ROM and Bootloader source code for HiFive1 be released any time soon?

Thank you!  
D

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**Author:** ![mwachs5](https://sea2.discourse-cdn.com/flex020/user_avatar/forums.sifive.com/mwachs5/32/13_2.png) [@mwachs5](https://forums.sifive.com/u/mwachs5)\
**Post date:** [December 30, 2016, 1:56am UTC](https://forums.sifive.com/t/otp-bootloader-source/214/2 "2016-12-30T01:56:00Z")

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OTP is 4 lines of assembly, which can be found in the Getting Started Guide. Will open source the bootloader and requested items soon after we’re back from the holidays!

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**Author:** ![donb](https://sea2.discourse-cdn.com/flex020/user_avatar/forums.sifive.com/donb/32/41_2.png) [@donb](https://forums.sifive.com/u/donb)\
**Post date:** [December 30, 2016, 2:15am UTC](https://forums.sifive.com/t/otp-bootloader-source/214/3 "2016-12-30T02:15:04Z")

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Thanks, Megan. Happy holidays!

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**Author:** ![bleepbloop](https://avatars.discourse-cdn.com/v4/letter/b/3e96dc/32.png) [@bleepbloop](https://forums.sifive.com/u/bleepbloop)\
**Post date:** [February 20, 2017, 7:22am UTC](https://forums.sifive.com/t/otp-bootloader-source/214/4 "2017-02-20T07:22:40Z")

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Any news for those interested in bootloader development?

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**Author:** ![mwachs5](https://sea2.discourse-cdn.com/flex020/user_avatar/forums.sifive.com/mwachs5/32/13_2.png) [@mwachs5](https://forums.sifive.com/u/mwachs5)\
**Post date:** [February 20, 2017, 3:47pm UTC](https://forums.sifive.com/t/otp-bootloader-source/214/5 "2017-02-20T15:47:04Z")

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The source for the “boot loader” shipped on the HiFive1 boards is available in the freedom-e-sdk, as double\_tap\_dontboot : [https://github.com/sifive/freedom-e-sdk/blob/master/software/double\_tap\_dontboot/double\_tap\_dontboot.c](https://github.com/sifive/freedom-e-sdk/blob/master/software/double_tap_dontboot/double_tap_dontboot.c)

To actually reflash the bootloader, you’ll need to tweak the linker script to start at 0x20000000 instead of 0x20400000, and lift the flash protection starting at 0 instead of 64 in the openocd script.

EDIT: Added link