F-16 ICP Analog Wheels

F-16 ICP analog wheels prototype works! That includes the PCB, MLX90316 chip, calibration, and programming of the sensor.

Inside is a ball bearing, an MLX90316 chip/PCB, a few screws and mechanical stop. It will rotate 340 degrees, and stopped by a mechanical stop made with a screw and a 3D printed stop. They are programmed in-situ to output about 0.02 to 3.259 V, depending on the variation in 3D printing. It's almost rail-to-rail. A little Windows calibration will do just fine. Also, the input power supply is 5V, but the MLX900316 chip is programmed to output between 0.0V to 3.3V (clamped at 3.3V) so it fits the voltage range of the RPi Pico (Pico has a 5V input, and a 5V output too, and I take power from the 5V output).

The two on the left are programmed to go clockwise rotation, and the right two are programmed to rotate counter-clockwise (increment), so that rotating up increases the voltage.

For the programming of the MLX90316 chips, I had powered up one of the old old old computers (circa 2007). I am just too lazy to install that clunky Melexis PTC software on another more modern computer.

BTW, the PCB for the MLX90316 is round, having an OD=1/2". Also, these 4 run in analog output mode instead of the nasty 3-wire SPI mode I hate, like what TM does. These are just wheels adjusting contrast etc., really no need to have higher resolution that can be gained from running in digital mode. 12-bit resolution of the output DAC of MLX90316 and the input ADC of the Pico should be plenty. No need for more resolution.

Oh, and I forgot to mention that this plate in the picture is "supposed" to be an aluminum plate, sheet metal, with 4 bended "ears" as the brackets of the analog wheels. However, I decided that it is too much trouble making it in metal. I mean, just look at the cut out for electronics. I just don't want to have yet another part that requires it to be out-sourced to OshCut, not that I don't like OshCut services. So, I fortified the thickness of the brackets... they still seem a bit fragile, but seem to work fine if you don't apply violence.





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