Archive for April, 2016

RoboPi Pure Python API & 64 bit RoboPi C library – it’s real close now!

Tuesday, April 26th, 2016

Raspberry Pi 2 Model B Review @

Good News:

  • pure Python RoboPi API works!
  • 64 bit C RoboPi API works!

Bad News:

  • readServo() in the firmware has a bug

Fixing the bug was trivial – the firmware returned two bytes too few for that packet.

I never found it as I have never used readServo(), a redundant function call in the API that reads back the last value written to the servo.

The native Python RoboPy library is more efficient than the previous Python wrapper against the C library, and uses less memory.

Looks like next week will have three software releases instead of two:

  • RoboPi firmware v0.95
  • RoboPiLib v0.95
  • RoboPiPyLib v0.95

There is no need to update your RoboPi firmware if you do not use readServo().

RoboPIC 18F4550 Build Manual posted

Monday, April 25th, 2016

I finished the RoboPIC build manual and added it to the RoboPIC 18F4550 product page.

RoboPIC 18F4550 Robot controller @
(click on image for larger version)

I followed the build instructions to make sure they work well – and to take the photos for the manual :)

Introducing Hobbit, Elf’s younger Brother! (2WD Raspberry Pi based Robot)

Thursday, April 21st, 2016

I think Elf was getting lonely, so I built a younger brother for him.

Hobbit @
(Click on image for larger version)

Hobbit is meant to be an inexpensive, yet expandable Raspberry Pi based robot.

Hobbit is based on Pi Droid Alpha, which not only incorporates a motor driver, but also avoids the costly eight core RISC microcontroller used by RoboPi – while preserving a lot of 5V digital I/O and providing an eight channel ten bit analog to digital converter for connecting analog sensors.

I will keep updating the Hobbit article as I add more software and hardware features – and the Elf article will also be updated soon :)

New pure Python library for RoboPi

Tuesday, April 19th, 2016

I’ve been working on a new Python library for RoboPi.

Raspberry Pi 2 Model B Review @

A pure Python library will allow me to support more platforms for Python RoboPi programming, as I don’t have to generate a new Python wrapper for the C library every time I extend the firmware or C library.

I expect to have it uploaded by Monday – I had to post because I was happy that I finally finished writing it :-)

PiDroidAlpha bug fix uploaded

Thursday, April 14th, 2016

Raspberry Pi Zero Review @
(click on image for larger version)

I’ve uploaded a new version of (RoboPi compatible library) to the Pi Droid Alpha product page.

I was working on a new Pi Droid Alpha based robot robot, and I kept getting “too many files open” errors.

The problem turned out to be some SPI access code in the library that opened the SPI driver – but never closed it. Ooops.

My new easy PWM motor control for RoboPi and PiDroidAlpha Python libraries will also be published real soon now :)