Tuesday, August 7, 2012

Checking out the new Cortex-M4 ARM core

I've been using the Luminary Micro Cortex-M3 core for awhile now. It's pretty cool, and has some nice power to it for when you're running more advanced stacks. I also started developing on TI's new Cortex-M4F Stellaris processors. The benefits of the new processors:
* Faster - standard up to 80MHz (though single-cycle flash only up to 40MHz)
* Floating Point processing
* Same or lower cost than the comparable Cortex-M3 processor
* Lower power - uses 65nm process instead of the 250nm process used on the M3 line

The best part of Stellaris (both old and new) isn't the chip, it's the software. StellarisWare is a hardware abstraction library for these processors and makes firmware development MUCH faster. It is pretty comprehensive (very few things you can't do in stellarisWare) and reasonably well documented.

The downsides of the Cortex-M4F:
* No Ethernet support
* Weird low power mode - "hibernation" but it doesn't keep the RAM alive, so you have to save your application variables
* Higher power consumption than MSP430.


  1. I'm delighted to hear that you like StellarisWare, Derek. Remember that we're always open to feature suggestions that you may want to post over on the Stellaris forum at http://e2e.ti.com.

  2. I've been using StellarisWare even more recently and really like it. I'd like the same for MSP430 too so I can write code for StellarisWare and have it work on the MSP430 too. I haven't played with MSP430Ware since it doesn't support the MSP430F2xx series which I mainly use. I'm on the e2e forums a lot to ask and answer questions.