Good news (http://www.arm.com/news/24418.html), Cortex-M0 is here.
I’m quite excited, because this is rock-solid ARM technology, and I’m expecting to see this puppy inside next generation devices all along. The fact that it’s small and simple means that it will be used in small and simple architectures, so I suppose that by the start of 2010 we will see a handful of products that mount it. The compatible instruction set means that software development will be easier, by reusing development environments and libraries.
Gate count: 12K. It’s small, very small. By comparison, Mentor Graphics offers 8-bit microcontrollers that are only 25% smaller. Easier to place inside an FPGA with other peripherals. Also, less gates means lower leakage current means lower power consumption.
DMIPS: 0.9/MHz. This is where Cortex-M0 is better than 8-bit microcontrollers. It’s important to measure the computing power of a cpu. If you create a CPU that consumes half the power, but it does the job in twice the time, you didn’t created anything useful: every CPU can do that, if you scale the clock frequency. A DMIPS around 1/MHz indicates that the CPU can perform common tasks using a decent (low) number of clock cycles. That’s what Cortex-M0 promises to do: get the job done efficiently and in a timely manner. This performance is achieved mainly because of the 32-bit architecture, that speeds up the processing by a factor of 4 (roughly and conservatively) respect to a 8-bit architecture. For example, typical DMIPS/MHz of 8051 architectures are one or two orders of magnitude lower.
Power consumption: 0.085 mW/MHz at 0.18um , 0.012 mW/MHz at 65nm. This is a fraction of the power consumption of its sibling, the Cortex-M3. By looking at the current battery specs we discover that for each 2 grams of battery we have a Watt-hour of energy before running out. That means that, at 50MHz, the Cortex-M0 will drain a 10 grams battery in around 50 days of full-time work.
In related news, I see that Evatronix is selling a 8-bit microcontroller (R8051XC2) with high processing power (up to 0.114 DMIPS/MHz) and low gate count (3K). These are the products that will make your tech-life easier. This is why the battery life of your mobile devices will last a little longer. Even if you don’t know they’re there.