Bluetooth Watt meter cockpit

TODO....

Bluetooth Watt meter cockpit

See also

• Maxun e-kit cable killer
• Bluetooth Watt meter cockpit
• Bluetooth Watt meter dongle
• Yamaha hacking dongle
• Two-wire current-controlled bus
• Sale on Tindie

Round meters vs LCD displays

I prefer round meters instead of text displays.

Round Bluetooth Wattmeter good readability in full sunlight

Wattmeter with LCD displayBosch ebike displays

Round gauges are easier to read, that is why many flight instruments are round, even the modern A380 glass cockpit displays round gauges on the LCD screen:

Round gauges at A380 glass cockpit

Eagle library for easily create a PCB with the addressable LED rings NeoPixel WS2812B-2020

I had to make a LED ring with WS2812B-2020 NeoPixel LEDs for a battery gauge meter. I wondered how I could align the LEDs in a circle as conveniently as possible. It is quite a lot of work to manually place the LEDs in a circle and also adjust the angles every time. Then I got the idea to create a special neopixel package where the reference point has shifted to the center of the circle. Now it is very simple, all LEDs have the same coordinates, you only have to set the angles to for instance 0, 9, 18 etc.

Eagle library for easily create addressable LED rings NeoPixel WS2812B-2020

Eagle package NeoPixel LED ring WS2812B 2020

Eagle library for easily create addressable LED rings NeoPixel WS2812B-2020

By the way, you can change the radius of the circle easily and quickly, you just need to move reference point in the package.

To obtain angles in natural number we are lucky that 360 degrees are divisible by many as 24 divisors. That is no coincidence, as the ancient Sumerians in the 3rd millennium BC already provided for this.

I also moved the SMD pads so that the connections are nicely aligned automatically; look at the drawing and you will see what I mean.

See GitHub for the files.

I bought the LEDs from Adafruit.