Source code usually resides on my github repositories.
For this particular project, the single C source file nfft.c is bundled in my breadboard collections repository. You just need nfft.c
Building the project
You can start w/ the breadboard layout. And it's ASCII art so may not be very clear. You can pair w/ the photo below to identify all connections.
The battery holder is made from a section of double male header pins. Use a pair of long nose pliers to pull out the middle pins, then bent the end pins to fit the two LR44 cells properly. Since there is no power switch, I use a thin piece of plastic tab to break the connection between the LR44s when not in use.
I am using mps430-gcc to compile the firmware but it should go well with TI CCS. You can avoid all the trouble of installing IDEs or compilers by going to TI CCS cloud, which is a web based IDE. I will even download the firmware to your target device.
msp430--gcc -Os -Wall -ffunction-sections -fdata-sections -fno-inline-small-functions -Wl,-Map=nfft.map,--cref -Wl,--relax -Wl,--gc-sections -I/cygdrive/c/Users/chrisc/Desktop/energia-0101E0016/hardware/msp430/cores/msp430 -mmcu=msp430g2553 -o nfft.elf nfft.c
I am using a TI Launchpad G2 as a programmer to program the MCU. I am not covering the installation / use of the tools as there are well written tutorials to cover that.