Capacitive Touch Sensing on the MSP430 – 2013 Edition
I took a look at capacitive touch sensing on the MSP430 in 2011 and it was a little… lacking. I had another project come up and had a chance to play around with it again a couple months ago. It’s nice to see the changes two years have made to the framework provided by TI.
I’m still using Code Composer Studio, but now we are at v5.5 on windows (Linux support is greatly improved since v4). The biggest change I made to get the code running was that when I copied the code out of the initial directory, I had to change the include path so that it pointed to the correct location. The capacitive touch framework is now included in the MSP430Ware package as the captouchlib.
My project involved using the MSP430 launchpad with a MSP430G2452 MCU and then attaching a proximity sensor to P2.0. The
RO_PINOSC_TA0_WDTp_Proximity_Sensor example matches this hardware configuration. I was very pleasantly surprised at how quickly I was able to get things up and running. I’d also like to give TI some credit for designing the library so that you can use it your way, not their way. What I mean by that is that all I need to do in my code is run the initialization and baseline settings for the sensors. After that, I just make a function call when I want the sensor read. It doesn’t make me use a huge, complex, some-what documented framework. This is much more accessible, especially for the beginner. Congratulations to TI. It wonderful what a difference two years make.