work

PWM Logger

What is it?

I designed the PWM logger to facilitate the development of small-scale autonomous vehicle systems whose performance strongly depends on servo data collection and then later, reproduction. Such as those who are implementing end-to-end ML systems.

It does this by decoding PWM signals from servos and motor controllers and then allowing an I2C master to record the readings to produce labels for a training set. The logger can also be put in a mode that generates PWM rather than recording. This way it can seemlessly swap between recording a human flying or driving, to letting the computer take the wheel.

What did I do?

I designed the PCB for the PWM logger in EAGLE CAD using the Parrallax Propeller as the MCU. I then programmed the PWM decoding and generation in it's native Propeller assembly. Finally, I wrote a software I2C driver in Propeller ASM to interface with other systems.

Learnings

Assembly programming
Hardware design, prototyping, assembly and debugging
I2C bus protocol
SMD soldering
PCB design

Technologies and Tools Used

Parallax Propeller MCU
GNU Make
EAGLE
Bus analyzer

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