GCC for the MSP430 might be worth looking at as well. I've never used that one, but I have used avr-gcc a great deal, and like it very much. I believe it's on sourceforge, Google should find it for you
The tools that come with the basic development kit from Ti are called kickstart. These include a full featured assembler and debugger from IAR, with a limited C compiler. IAR are a compiler vendor, they hope you will pay US$2000 for their full version of the compiler that doesn't have these limits.
There are many alternatives to the IAR compiler now available. The most common of these are MSP-GCC, a free set of tools that require some effort to get up and going for a compiler/GNU novice,and which, being open source are supported on an ad hoc basis by users. The most common commercial compilers other than IAR are (prices are my best guess):-
ICC430 from imagecraft. About US$199, if anything like Imagecrafts other products, and from what I see in the news groups, very well supported, but possibly not quite as 'full' as some products.
AQ430 from Quadravox. About US$299. Very well supported, seems to have everything but may not produce quite as compact or fast code as CCS?.
CCS430? From Rowley associates. About US$700. Paul aggressively supports his products, like the other vendors mentioned. From watching the yahoo msp430 group this would currently appear to be the technical leader amongst all the compilers, including IAR, with sophisticated code optimisation features.
All of the guys mentioned above are active in the msp430 group, all support their products very well, all offer some form of unlimited function trial period (ie no code size limits), all seem to have large groups of fans that for theeeir own reasons favour one or the other vendor.
I suggest you try each product and pick your favourite, after all it'll cost you nothing to try them.
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