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Armstrap Claims to Make ARM Prototyping Easier (Video)
It almost seems too perfect that the originator of the Armstrap 'community of engineers and makers' is named Charles Armstrap. He just introduces himself as 'Charles' on the Armstrap.org website. Names aside, Armstrap.org is 100% open source, including circuit board designs. This is not a 'draw your own circuit boards' bunch, although you certainly could if you wanted to badly enough since they provide schematics and even full CAD drawings of what they make. The reason they do this is laid out on their Core Values page. The boards Armstrap sells are not expensive, but if you are going to be truly open source, you need to supply the means to duplicate and modify or extend your work, as is totally permitted under the MIT License they use.
I've developed many applications for Arm based systems and anything that gets more people involved is an excellent way to make the platform more well polished and increase the market share not only for the Arm platform but for Linux as well.
ST makes several ARM M4F based dev/eval boards with built-in JTAG and a few additional chips thrown in to play with (I think accelerometers and MEMS microphones are common). They cost around $15-$20... go to http://www.st.com/web/catalog/... and check the box for STM32F4 under Supported Devices.
So, with what I suspect is the benefit of manufacturer loss-leader subsidies on the Discovery boards, why would I spend $40-$60 more on a dev board?
ARM has two general series of processors, the A series, or application processors, and the M series, or microcontrollers. Microcontrollers (such as the STM32F4 in the Armstrap boards) are designed for low-power embedded device use, you *might* run a specialized RTOS on one, but usually it's just your code, running bare-metal. An application processor, such as what you have in your smartphone or in the Pi, is a more general purpose computing core, running faster, taking more power, and using a full OS for resource management and process scheduling. Also, generally, microcontrollers have their own built-in RAM and Flash, while application processors use external RAM and storage (the Pi looks like the RAM and CPU are one, but in reality they're two separate dies, stacked up within the same package, while micros have everything on the same die).
This board, http://developer.mbed.org/platforms/ST-Nucleo-F401RE/ , based on an STM32F401RET6 costs $10 dollars and has a HUGE community with a great set of libraries, on-line IDE. And if you want you can use the MBED libraries with an offline toolchain.
I don't understand why one would mess with the Armstrap Eagle. Ok, maybe to build my own board with modifications since they provide the Eagle files.
A new troll is born, always a beautiful sight.
To have a right to do a thing is not at all the same as to be right in doing it
They're also awesome. Think of them like the AVR or PIC with more.. everything. More RAM. More ROM. More IO. More interfaces, both type and quantity. More Hz. Same price, they work with GCC.
I've been getting STM32s from china for cheaper than the basic AVRs on an arduino (not sure how, as even qty 1000 is like 4x the price on digikey, but they work like the real thing, so who knows?!).
I used to love AVRs, but whenever I go back to them now, they seem so limited. the ARM MCUs have a bit of a learning curve, but it's so worth it. With GCC and libopencm3, it's an entirely open source setup. The nucleo boards are dirt cheap arduino-ish things, to get started on, with integrated programmer & debugger.
There's really no reason to use 8bit MCUs anymore, unless you're making a $0.40 gadget, and need to squeeze out that last nickel.
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