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Recently I've been doing a lot of work with STM32L. The asynchronous RTOS that I had previous built for MSP430F5/F6 is now working nicely on STM32L. I'm doing some benchmarking and profiling of STM32L vs. MSP430 -- it is a long process, but the signs aren't looking good for MSP430. Here are some of the preliminary, qualitative results. Lowest-Power Sleep: I've used LPM3 for MSP430F5 and STOP-mode for STM32L. These are the lowest-power modes that allow SRAM retention (and register retention) and a means for the MCU to schedule its own wakeup with a timer. Both of the devices use roughly 2uA in this mode. Both devices also come out of lowest power sleep in roughly 10us, however the MSP430 needs more like 100us if you have the supply voltage monitor enabled. STM32L does not need the extra time, so it wins. Runtime Performance per mA STM32L is using the Cortex M3, not the M0, so it has a brutish ALU with 32x32 multiplier in addition to single-instruction multiply-accumulate, single-instruction logical comparsion with shift, and a bunch of other neat ALU instruction that make it run very fast. Additionally, it has a DMA that is independent of the CPU. I'm using it a 4.2 MHz to achieve 1mA runtime, and my MSP430F5 is running at 5.2 MHz to achieve 1mA. For doing DSP or software crypto (like RSA), it isn't even close. The ARM just humiliates the MSP. For doing protocol processing, RTOS scheduling, and more logical operations, the ARM still is beating the MSP by about 2x, even though the MSP is clocked a bit higher. So, my verdict is that STM32L uses less than half the runtime power of MSP430F5. STM32L also has a fast-settling 16MHz clock that outperforms MSP430 at 25MHz, and if you're crazy you can push it to 32 MHz. It absolute performance, it just dominates. Features and cost I'm comparing a low-end STM32L (STM32L151C8: 64KB Flash, 4KB EEPROM, 10KB SRAM) and a mid-range MSP430 (MSP430F5510: 32KB Flash, 0.5KB storage Flash, 6KB SRAM). Otherwise, they have a comparable set of peripherals and they cost about the same. The difference is that almost every peripheral in the STM32L is just a little bit better than its equivalent on the MSP430. Plus, having the 4KB EEPROM is really nice. The storage Flash is still NAND-type Flash and it still needs wear-leveling, which is hardly worth the effort for such a small piece of memory. The sole redeeming factor of MSP430 A major deficiency of STM32L is that there isn't a low-power clock source other than the RTC, so building a low-power asynchronous RTOS is difficult. But, it is obviously possible. Moreover, chips like EFM32 are nearly identical to STM32L, except even lower power, and EFM32 has an array of low-power timers. MSP430 has a much better clocking system for implementing low-power apps, and overall it is a lot easier to work-with than STM32L. But now that my RTOS is ported, that hurdle is cleared, so the ease-of-use argument is really not a huge deal, in my opinion. What's left for MSP430? Frankly, I'm not bullish on MSP430 anymore. I've used it for years, I think the architecture is very elegant, and I love the clocking system. The competition from Cortex-M is just getting to tough for any mid-range "proprietary" MCU architecture to face. It's not just TI: everyone making competitors to Cortex-M is getting squeezed. The Wolverine core is a nice move by TI, but it's too little too late. For the same price as a Wolverine core MSP430, I can get an EFM32 with superior MCU features apart from the FRAM, and similar or even superior low-power features. These EFM32s have 16KB of SRAM and a really good supply monitor, so all you are really getting with FRAM is a speed-limiter on your CPU (8 MHz). My conclusion is simple: TI needs to find a way to drop the price on MSP430 so they can compete in the low-end market against AVR8 and PIC, where the MSP430 is faster and lower-power. Today's mid and high-end MSP430's simply cannot compete against Cortex-M. TI has always been about beating competition on marketing and fabrication, so I know they can do it, and I'm surprised they haven't. Clearly, the G-series is a step in that direction, but in my opinion it is really it is the 5-series that they need to cost-optimize.