• Home
  • About
  • Resume

Category: New Stuff

Persistent configs in Rocky.js watchfaces

By , 02/09/2016 10:56 PM

Rocky.JS is the first step in Pebble journey to run JavaScript directly on the watches (unlike Pebble.JS which runs on your phone). Previously I described how to convert a simple watchface from C to Rocky.js. But that was a static watchface with unchangeable settings.

Here I will show how to create a configurable watchface in Rocky.js similarly how classic SDK faces can be configured. You will be able to reuse your existing config page – and if it was set to work with Pebble emulator as well as real watch – you will reuse it without any changes at all.

First let’s review how classic Pebble SDK calls config page. In PKJS (JavaScript) portion of Pebble code usually there’s a piece like this:

  function(e) {

If user requests config of face/app – this event fires and opens page with configurable options from specified URL. After user modifies settings usually “Save” button is clicked on that page and code similar to this executes:

$('#xbtnSave').click(function () {
   var location = (decodeURIComponent(getURLVariable('return_to')) || 
                   "pebblejs://close#") + 
   document.location = location;

Here, first we determine which location to redirect config page to. If parameter "return_to” is passed in query string (here custom function getURLVariable() is used to extract individual parameters – look it up), so if this parameter is passed – it means config page is called form the emulator and we use it for redirection. Otherwise we use standard "pebblejs://close#" URL to save settings into real watch. We also take settings object which has our collective options combined, convert it to string and add to the URL as a parameter. Page then is redirected to resulting URL and Pebble emulator or real watch takes care of processing parameters.

So, how can we (re)use it in a Rocky.js watchface? Continue reading 'Persistent configs in Rocky.js watchfaces'»

Rocky.js – Pebble watch coding in JavaScript

By , 02/08/2016 3:59 PM

Pebble never ceases to amaze. And every time you think – this is it, they reached the pinnacle of awesomeness – they surprise you again. This time they did pretty much the impossible – ported their C SDK to JavaScript, by creating Rocky.JS project. Ultimate goal is to run JS directly on the watch hardware – this will open way to huge number of new developers who hesitate to dive into depth of C. Meanwhile it provides ability to run Pebble code directly in a browser! It’s a lot of fun and as a bonus you can insert Pebble watchfaces directly into your website as evident by living watchface you see here.
Watchface you see running above is called Meyer Object it’s been available for Pebble watch for a while and I decided to port it to Rocky.JS Continue reading 'Rocky.js – Pebble watch coding in JavaScript'»

Restore natural picture look on Samsung smart TV

By , 02/02/2016 10:04 PM

I really like my new smart TV from Samsung it has tons of bells and whistles. But one thing I noticed – no matter what I watch – series or movies, streaming or broadcast – picture has a “teleplay” feeling – like the action is happening on stage in the theater. If you recall what later Twilight Zone episodes look like you’d know what I am talking about. Maybe it’s supposed to look like this, but I like “film” feeling more. So I found a setting that restores natural picture look:

Go to your TV menu, then select Picture -> Picture Options -> Auto Motion Plus and turn it off.

Fix Roku problem connecting to 802.11ac 5Ghz WiFi

By , 01/30/2016 2:15 PM

I recently got a Roku 4 – at the time of this post the latest and greatest streaming players from Roku family. It comes with many bells and whistles – including ability to connect to 5Ghz WiFi networks. But for the life of me – it could not connect to mine. Player was seeing the SSID of the network, able to connect to wireless, but chocked on joining to LAN. Extensive chat with support lead nowhere – they wanted me to change WAN DNS and many other hoops that achieved nothing. For the record – my router is a dual-band one, and Roku had no problems connecting to 2.4Ghz band. But Internet speed falls dramatically over 2.4Ghz connection and I needed 5Ghz.

Finally I found one thing that worked.
AC Network
AC connection has 3 bandwidth modes: 20Mhz, 40Mhz, and 80Mhz. My router was set to 80Mhz to take full advantage of 1300 speed. None of my devices had problem with this (including, I might add, my previous Roku 3 player). But apparently Roku 4 couldn’t handle it. But as soon as I switched bandwidth to 40Mhz – boom, instant connection.

Streaming doesn’t suffer from this change, but it does lower LAN speed, so I’d like alternative solution from Roku if possible. Is this a known issue? Would an update fix it?

UPDATE 2016-02-01: Found a better workaround with the help of this awesome device.
WUMC710 is a bridge between 4 Gigabit Ethernet connections and full 802.11ac WiFi. And it has no problem with 80Mhz channel. So I basically tell Roku it has a wired connection (and it does to the bridge) and the bridge has beautiful wireless connection to my router. You can grab the WUMC710 pretty cheap (I got mine for $10) and besides not having to slowdown your main network it makes actual Roku internet Speed much faster. Shame Roku’s own WiFi is not on par, but hopefully it will catch on

Solved: Issue with Pebble framebuffer after notification is dismissed

By , 01/08/2016 1:15 PM

Effect Layer Issue I’ve encountered a weird issue while working with EffectLayer Library (a visual effect library for Pebble smartwatch). In this particular watchface called Clean & Smart I used “invert” effect which inverts colors of the watchface should the user choose that option in settings. It was working fine when option changed when watchface was loaded/unload and behaved weirdly only in one particular scenario: when you would receive a notification (email, text etc.) and then dismiss it. Upon coming back from notification to watchface invert effect would only partially cover the watchface (as seen on the screenshot).
I don’t know exactly what was happening, but had a theory. Continue reading 'Solved: Issue with Pebble framebuffer after notification is dismissed'»

How to make your Pebble smartwatch really tick

By , 08/18/2015 1:28 PM

“Tick tock, goes the clock, And Now what shall we play?”.

Pebble smartwatch is an amazing piece of hardware with no less amazing software to support it. Pebble appstore boasts huge variety of watchfaces from intricately carved art pieces to simplicity personified. And the apps, my gods the apps! You want to track your sleep, count swimming stokes, automate your home – Pebble can do all those things and more. But something was missing. Something that ordinary mechanical clocks could do since the dawn of time.

Tick tock, goes the clock, And then what shall we see?
Continue reading 'How to make your Pebble smartwatch really tick'»

Solution: Windows 10: Unable to start Appstore apps

By , 08/05/2015 1:45 PM

Ok, I went ahead and upgraded to Windows 10. everything went smoothly, all my settings and installed apps preserved and work without a hitch. I am loving the interface and getting along with Cortana pretty good.

But after a while I encountered a weird issue: Appstore installed apps – e.g. Calendar, Mail etc. even Windows AppStore itself wouldn’t launch. I’d either get a cryptic error message, something along the lines “Application did not start, please contact system administrator” or very briefly a window would appear and immediately closed.

Looking into Event log was a bit more explanatory, but not too much: “Microsoft.WindowsStore_8wekyb3d8bbwe!App failed with error: Access is denied. See the Microsoft-Windows-TWinUI/Operational log for additional information.

If you google it – you will find many possible explanations of the problem and many possible ways to solve it offered, but none of those worked for me. Finally I figured it out (and Event Log entry gave me a clue): C:\Program Files\WindowsApps folder was missing necessary permissions:


Namely, “ALL APPLICATION PACKAGES” was missing read & execute permissions on that folder (had to to uncheck “Hide protected operating system files” in Control Panel, File Explorer options to be able to see it). Once I added correct permissions – appstore apps started launching with no problems.

Pebble NYC Meetup

By , 06/26/2015 9:08 AM

Pebble had a first NYC developer meetup on June 24th 2015 and yours truly made a presentation about EffectLayer library there. Enjoy!

“Background” vibes on Pebble smartwatch

By , 05/21/2015 4:17 PM

Matt Thompson from Pebble G+ community asked a question that got me curious: Is there a way to buzz Pebble vibe at regular intervals in the background, while a regular watchface is displayed in foreground?

Besides running a normal app, Pebble has 2 ways to run code in the background: background worker and Wakeup API.

Background worker can truly run in the background, but has no access to UI (and vibes are considered UI) as well as other limitations. Besides you can have only one background worker, so for example if you’re running MisFit app and want to run another background app – you’re out of luck.

WakeUp API has the ability to act as a timer in the background and launch your app when timer countdown finished. Interesting thing is – if your app doesn’t have any UI (windows) – it exits right away, so from the user’s point of view – it didn’t even ran – then point in the watch interface remains the same (if you’re looking at a watchface, or at settings etc. – you remain at the same spot).

We can use this to wake the app, buzz the vibe, reschedule wakeup time and exit. User will just hear a buzz with no visual indication that something was launched. Here’s a basic code to achieve this:

static uint32_t const segments[] = {1000, 500, 1000, 500, 1000};  

static void init(void) {

  wakeup_schedule(time(NULL) + 60, 0, false);
  VibePattern pat = {
    .durations = segments,
    .num_segments = ARRAY_LENGTH(segments),

int main(void) {

This is pretty straightforward. Line 01 declares an array for custom vibe pattern (3 one-second buzzes separated by half-a-second silence) Line 05 subscribes to WakeUp event. Ordinary you need to specify a callback function as a parameter, but our entire code runs in the Init, so we don’t use it here. Line 06 schedules app wake-up in 60 seconds. Line 08 cancels any current vibes in case any are still running. Lines 10-13 prepare structure for custom vibe sequence and Line 14 runs the vibes.

That’s it. When you launch the app – it schedules its own wakeup, buzzes the vibe and exits immediately. You’re free to do what you want – set a watchface, run another app etc. When time comes – the app wakes up, buzzes the vibe, schedules next wakeup and exits without interfering with whatever user is doing. Etc. Etc. Etc.

Just remember that the only way to stop it is delete the app from the watch and wait for the current buzz sequence to finish.

Useful Links

Colorful watchfaces for Pebble Time

By , 05/13/2015 7:50 PM

Pebble Time is latest and greatest smartwatch from Pebble corp. And one of the advantages it has over classic model is new epaper screen capable of supporting 64 colors. To test its capabilities I developed several color watchfaces. Some of them are the converted ones that originally were made for classic Pebble, some of them new. Click on the image to get redirected to Pebble appstore.

Long Shadow “Long Shadow” – inspired by stock LG G watchface, features large time and long colorful shadows. Config page allows customization of every color as well as shadow direction
TV Time “TV Time” – old-style TV displays time in cartoon format. Grid on the panel shows battery level
Simpe Striped “Simple Striped – Large time in color-striped font. Thin line at the bottom shows battery level both in length and coior
RusticSlider “Rustic Slider” – Though not in full color, uses Pebble Time gray shades to create realistic blocks with customizable sliding animation
Poochie “Poochie” – spoof of Gucci luxury digital watch
MeyerObjects “Meyer Objects” – Hour. minute and second hands are represented by wireframe design. Shake to display normal digital time. Configurable options
3D Wedge “3D Wedge” – Time displayed in diagonal skewed form along with date, time and battery percentage

Give them a try once you get your PT! Or, you can load them on your classic Pebble as B&W versions 🙂

Panorama Theme by Themocracy