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Rebble Community Update 3

“Where is my Rebble Community Update?” the people cry! At last, it is here, and this time, rather than the typical broad yet shallow summary, we thought we’d take a closer look at a particular area of import: firmware. Familiarize yourself with our feats in this forward-looking firmware-focused feature. If you’d like to add something, send us a tweet, or better still, submit a pull request! :bowtie:


While the Pebble/Rebble ecosystem is comprised of many parts: hardware, appstore, mobile apps, watchapps/watchfaces and more - one of the most critically important pieces in terms of keeping existing hardware alive is developing replacement firmware. Since the original Pebble firmware was not open source, and is owned by Fitbit, this unfortunately means starting from scratch. Not completely from scratch, since the FreeRTOS operating system on which Pebble OS is based can be leveraged, and moreover an example implementation supporting the STM32F4 family of microcontrollers on which the Pebble Time and subsequent hardware is based was able to serve as a basis for exploration of Pebble’s specific hardware implementation(s).

Part of the reason that an update has not been forthcoming is due to the continual advances being made, so that each milestone at which sharing seemed appropriate ended up being dwarfed by additional progress made before it had even been possible to share the last! Here’s a detailed breakdown of where things are today (who knows how much further along they’ll be tomorrow!):


Beyond the low-level hardware interfacing work, there is a lot of software that has to be written before “basic” functionality such as drawing shapes and text is possible. With this in mind, @jneubrand began work on neographics, an open-source replacement for Pebble’s graphics routines, long before there existed firmware sufficiently advanced to support it. @ginge was then able to drop this code into the firmware, once low-level display support had been developed, and the combination of graphics primitives, fonts, and now image loading (once the various palletised PNG bit-depth formats had been accounted for) allowed for the working system app and even watchfaces seen here:

@NiVZ78 created the Simply Squares watchface depicted above, to which @ginge added colour, as a way for RebbleOS to show off its new capabilities. While we’re not yet able to dynamically load watchfaces (what’s pictured, while being a legitimate watchface, still had to be compiled into the firmware), extensive new API support means that the following app-enabling features are now available in Rebble OS:

  • Graphics (drawing, lines, fill, etc)
  • Layers
  • Bitmap layers
  • Text layers
  • Bitmap API
  • Sub bitmap
  • Text / Pebble fonts


@ginge’s focus has been on Snowy, more commonly known by those not actively involved in firmware development as Pebble Time. Snowy support has begun to extend beyond the basics, including the ability to access the external flash, enabling resources, fonts, and images to be utilized. The I2C interface to the Maxim MAX14690EWX has been implemented, as has the ambient sensor, though it is currently unused due to experiments in dynamic dimming not having gone particularly well. Backlight has come on strong (then gradually faded!), however, as evidenced in this video.

Tintin, more commonly referred to as Pebble Classic or OG now has basic platform support as well, including support for its display, thanks to a number of contributions from @jwise - although the lack of flash support means no graphics. @jwise also did wonders with the Makefile and build process, facilitating testing and contribution from others (there was a magical moment earlier this week when a new contributor posted a picture of the firmware running on actual hardware within a day of his first introduction into the community!).

The Road Ahead

As exciting as everything we’ve been able to demonstrate so far is, there’s still a lot to do! Power management for example - the hardware is currently running at full speed, resulting in battery life of around five hours - and that’s without all peripherals even having support yet. Other basics such as a viable Bluetooth stack are still all to do, although @XDjackieXD has begun investigating solutions. A casual list of remaining TODOs can be found on the repo’s wiki. Embedded engineers, especially those with FreeRTOS experience, would be more than welcome to join our efforts if you’re interested! :bowtie: :heart:

Hopefully you found this detailed look at the state of Rebble firmware insightful and informative. If you have questions or would like to get involved, come and find us in the #firmware channel on Discord!

News and Miscellany

  • The fabulous folks at Fitbit have released updated versions of the Android and iOS Pebble apps which aim to free Pebble devices from existing tethers to cloud-based services; the most exciting part of this is added support for pebble://custom-boot-config-url/CUSTOM_URL - essentially a direct gift to Rebble, allowing us to override and replace the official appstore when it goes offline (which we’d already made strides towards, but official support is especially appreciated! :heart_eyes:)
  • Keep an eye on the Status page - while we originally intended for this to be a summary of how Pebble’s backend services’ availability would impact usage of our devices, we’re planning on expanding it to convey at-a-glance summaries of our own project and services’ status, as a way to provide updates between…Updates! :sweat_smile:
  • Our good friends at Engineerable are offering members of the Rebble community $20 savings on any TimeDock order with discount code Rebble! :gift_heart:

Rebble Community Update 2

Welcome to the first Rebble Community Update of 2017! Please peruse our paraphrased prospectus of progress over the preceding period. If you’d like to add something, send us a tweet, or better still, submit a pull request! :bowtie:

It’s been over a month since our last update, though the lack of updates here belies the tremendous strides made across myriad projects! While our early efforts concentrated heavily on investigation and reverse engineering, often manifesting as wiki pages and rough proofs of concept, many projects are starting to mature into tangible, viable entities. The Rebble Store now has a live, functional front end, with the required back end to support it well underway. Firmware has moved beyond emulation and onto real hardware, with promising demos on both Pebble Time and Pebble Steel. Replacement graphics libraries and fonts are being scratch-built for inclusion in upcoming firmware. There have even been pics posted of what appears to be some kind of new Pebble-esque prototype! Details, source code links, videos, and more below… :rocket:



Mobile Apps

News and Miscellany

Rebble Community Update 1

A cordial hello, and welcome, to our inaugural Rebble Community Update! Herein lies a casual compendium of recent activity within the community. If you’d like to add something, send us a tweet, or better still, submit a pull request! :bowtie:

Not even two full weeks have passed since Pebble announced their closure, and already the community has made massive strides across all targets! Documentation has flourished, with over 100 total commits to the wiki. Scratch-built iOS and Android apps are underway, and the official iOS app has been successfully duped into loading the Rebble Store. Speaking of the Rebble Store, the front end has been largely completed, while efforts to marry it to back end functionality are underway. And apps themselves are free to roam thanks to MPUless firmware, while the firmware team also attacks from the other direction with scratch-built firmware and custom FreeRTOS capable of drawing to the Pebble Time’s display. Details and links to more information for these projects and more are included below.




Mobile Apps

News and Miscellany

Rebble: Pebble Reborn

The Pebble smartwatch has meant a lot of things to a lot of people. From a strong leadership position at the forefront of what seemed like a smartwatch revolution, Pebble emphasized simplicity, and complementing the computer you already carry in your pocket instead of replicating it. Eschewing touchscreens for tactility, power-hungry OLEDs for power-sipping always-on LCDs, and embracing multiple platforms while others targeted just Android or iOS, Pebble has always focused on what matters most to users, and as a result, a vibrant community of fans quickly formed around them. A well-fostered subset of that community were developers, attracted by Pebble’s fantastic documentation, delightful SDK, and general amazing treatment of developers. Realizing as I type this that some of the preceding links may soon stop working following Pebble’s shutdown is incredibly disconcerting. Yet these feelings of unease and uncertainty have been harnessed by the developer community to create our own next chapter in the Pebble story - a chapter that we have decided to title Rebble. (shout out to @Northeastpaw on the officially unofficial Pebble Dev Discord server for advocating this name!)

Since the rumours began, and only increasing with their confirmation, a groundswell of support from developers and the community at large has resulted in countless suggestions, ideas, and projects to extend the Pebble legacy beyond its fateful denouement. The aim of Rebble is to bring the many disparate efforts under a single banner, concentrating energy and enthusiasm to maximize the likelihood of continuance and resurgence of Pebble as a platform. There are a vast quantity of extremely talented individuals ready to commit their time and expertise to extending the longevity of our wrist-based companion, from app distribution to hardware reverse-engineering, from archival to revival, from community to companion apps. Browse this site to find out more about our current projects, our ever-growing team, and the knowledge we’ve amassed so far. Peruse the FAQ, then please, sign up for our newsletter, join the #rebirth channel on the officially unofficial Pebble Dev Discord server, or just send us your ideas and words of encouragement via Twitter. Pebble’s tangible assets may have been liquidated, but its greatest asset of all, its amazing user and developer communities, endure, rebelling against our assumed fate, and seeing our wonderful little wearables reborn! :triumph: