Apr 212013
How to use soft PWM in RPi.GPIO 0.5.2a pt 2 - led dimming and motor speed control

In part 1 of this series, we looked at the basic commands for using software pulse-width modulation (PWM) in RPi.GPIO 0.5.2a and higher. In this article we’ll get a bit more hands-on and into some practical applications for it. It’s all very well being able to make nice square-wave pulses on an oscilloscope, but what’s it actually useful for? Our servo said? EEEEH AAAAH I tried using RPi.GPIO soft PWM with servos in response to a query after the last article, but, although it did change the servo positions, it was jittery. Servos require quite […more…]

Apr 072013
RPi.GPIO 0.5.2a now has software PWM - How to use it

Over the last couple of weeks the pace of development for Python programmers who like to dabble in GPIO has gone up a gear. Both main GPIO systems for Python on the Raspberry Pi have been getting some enhancements. RPi.GPIO, now at version 0.5.2a, has interrupts and threaded callback capability. You will probably have seen my three recent posts showing how to use those. WiringPi for Python version 2 is in Beta testing. I discovered two bugs while I was trying it out. Both of those have been squashed. One by Gordon “Drogon” Henderson in […more…]