It is the story of repurposing a broken Garmin watch into a desktop notification display. When focused on a computer task, don’t miss any notifications thanks to the absurdity of a desktop notifier.
Some time ago I struggle to make a small device displaying the phone notifications on a nice display. I tried with an ESP32 linked via Bluetooth to a custom app on my android phone. For example Mitchell Wong Ho made a nice project doing exactly that [link]. Unfortunately I didn’t manage to get reliable automatic re-connection after I got away with my phone.
Garmin makes very nice smart watches. And their phone application is full of features. You can have all the notifications you want on the watch’s display, and the connection is reliable. After detour from eBay, and I found a small Garmin vivosmart3 watch. The display is broken, but seems to still connect to a phone. And more importantly, it was very few euros.
The display of this watch is a monochrome OLED, 128×64 pixels. And here some of you might start to think of having a look on the data. To understand the data sent to the screen, I had to made a break-out board for the small smt connector. It was easy then to connect a logic analyzer. It is a SPI connection, so I started to program a PIC18F57K42 to forward the bytes to a serial port. Playing with some offsets reveals the image.
I have laying around some nice 128×64 VFD display I used for the Thermal printer project. Their connection is serial at 115200 bauds. So I programmed the PIC to act as slave SPI and Serial master, and put in form the data.
The display module is quite large, so I draw a case that looks like a 70’s TV set.
Remains 3D printing and stuff everything inside :
3D files and PIC program can be found here.
Thanks for reading!