BerkeleyX: EE40LX Electronic Interfaces Module 1

I just started the Berkley edX course on Electronic Interfaces.  The ultimate goal is to build a small robot and they give you latitude along the way on how to build it.  At the end of Module 1 (just before the quiz) you put together a voltage regulator to power the MSP430G2 from a battery.  Here is mine, running the hello world sketch:

Their design calls for a 9V battery and a LM1086 3.3V voltage regulator.  I'm using a LD1117AV33 and a 4xAA switched battery pack because that is what I happen to have on hand.  I made 100 on the quiz.  So far, so good...

Stripped down Stand-alone M430G2553

It is amazing how easy and inexpensive it is to program a MSP430G2553 (or any number of other chips in the value line series) and then run it as a stand-alone microcontroller.  The photo below shows a MSP430G2553 being programmed with a MSP-EXP430G2 LaunchPad.  The LaunchPad costs $9.99 at Mouser.  The MSP430G2553 costs $2.80 as a single, $2.25 if you buy in lots of 10. 

This is a minimal setup to program the chip.  Once it is programmed, you can remove the TEST and RST jumpers.

Thanks to Kerry Wong for his write-up here that I used to get started.  I've simplified his set-up by leaving off RXD and TXD, and taking the pins directly to the LaunchPad.  I took off the jumpers on the LaunchPad and hooked-up to the pins on the LaunchPad the same as Kerry.

Here it is blinking "hello world" from a battery pack. 

RGB Strip LED

For my sound level project I am considering using inexpensive RGB Strip LEDs.  So to try some code out I did a trial from this Adafruit post:
https://learn.adafruit.com/rgb-led-strips/overview

The differences are:

* used Adafruit's circuit for the TIP120 except except that I used 5mm LEDs to stand in for the strip (also put a resistor in front of each LED so it wouldn't burn out)
* used Adafruit's sketch except I substituted pins 11, 12, and 13 for the Arduino PWM (used a MSP430G2553)
* used a 4.5V battery pack for external power to the LEDs

It is working:

For my project I am thinking I'll need at least 2 strips running 2 different colors so 6 TIP120s.  I only have 5.  Even better would be to have 3 strips and 3 colors - then I'll have the added complication of not enough PWM pins.  It looks like there is another order in my future.

What this blog is about....

I'm a mechanical engineer, new to microcontrollers.  I started out with Arduino, but one day found myself with a new TI MSP-EXP430G2 LaunchPad and not much idea of what it could do.  What I've found is that in the LaunchPad series there is a board that can do anything Arduino can do and a whole lot more.  Just one problem... the support at the beginner level is not as developed as that for Arduino.

My objective with this blog is to document some of my experiences with the hope it will ease the process for others getting started with the LaunchPad series.  The LaunchPads I tend to use the most are the MSP3200 (for internet) and the MSP-EXP430F5529LP (for general purpose).  In addition, I can see use for the MSP-EXP430G2 where I want to embed a small board into something.  I have a MSP-EXP432P401R now and I look forward to learning a bit more about the real time operating system (RTOS).