Moving to Linux
As a professional embedded programmer, I wanted to
write all of the control software in C using the least amount
of resources. Low resource usage equates to low power. I
abhor a mechatronic device that takes 30 seconds to boot
up. Less than 100 msecs is the average time it takes to boot
a lightweight real time OS, so why would I want to use
Once we became a team, it was more important to be
able to divide the software tasks up. We each have
specialized skills. Chris is an animation and AI specialist.
Girts excels in data communications and robot simulations.
Even though Linux is slow to boot and consumes a great
deal of power compared to a lightweight OS like FreeRTOS,
it does have the advantage of easy collaboration among
developers. Moving to a Linux-based system was difficult for
me as a firmware purest, but the benefits outweighed the
The other team members were experimenting with the
Raspberry Pi. This was a good affordable platform for our
software. The problem with the Pi was with its lack of
peripheral interfaces. It only has one serial port. Each one
of Watson’s legs requires one load cell interface box that
reads the cells and converts the raw data into millipounds.
To read both leg’s data requires two serial ports.
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