# Flashing Gsender firmware

**URL:** <https://forum.pwncnc.com/t/flashing-gsender-firmware/3641>\
**Category:** Sienci Labs\
**Tags:** troubleshooting\
**Created:** [January 16, 2026, 12:57pm UTC](https://forum.pwncnc.com/t/flashing-gsender-firmware/3641 "2026-01-16T12:57:35Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![greenram](https://yyz1.discourse-cdn.com/flex011/user_avatar/forum.pwncnc.com/greenram/32/1710_2.png) [@greenram](https://forum.pwncnc.com/u/greenram)\
**Post date:** [January 16, 2026, 12:57pm UTC](https://forum.pwncnc.com/t/flashing-gsender-firmware/3641/1 "2026-01-16T12:57:35Z")

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I’m having control issues and have tried flashing the firmware in Gsender (1.5.7). The flashing process is asking for a hex file. I have no idea where to find a hex file.

I’m running a Sienci Labs Longmill MK2 48X30, SBL EXT. Just installed closed loop stepper kit.

Thanks, Chuck

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<div class="post-metadata">

**Author:** ![DocM27](https://avatars.discourse-cdn.com/v4/letter/d/f05b48/32.png) [@DocM27](https://forum.pwncnc.com/u/DocM27)\
**Post date:** [January 17, 2026, 3:03am UTC](https://forum.pwncnc.com/t/flashing-gsender-firmware/3641/2 "2026-01-17T03:03:19Z")

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You can get the firmware (the hex file you are referring to) here. Read through and follow the instructions.

> **[Firmware & Flashing - SuperLongBoard](https://resources.sienci.com/view/slb-firmware-flashing/)**
>
> Page Suggestions? Your board will likely ship with the latest firmware already installed, but we occasionally make updates to add new features or address any discovered issues. You may also choose to re-flash the firmware onto your board if you've...