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Comment by ksec | Hacker News Reader

Suggested Price @ 0.75 Per Unit at 100K Batch.

Would Love to get one to play with :D.

You can get a FRDM-KL25Z dev board with a 48Mhz M0+ for $12.95

It even works with the Mbed system, so you don't need to worry about setting up a compiler environment becuase you can do it all online (unless you want to - it works with GCC)

http://mbed.org/handbook/mbed-FRDM-KL25Z

Shameless plug: I've written a program that combines a terminal (for the Freedom board's debugging serial output) with one-click uploading of newly build code. It's called Freemon, is GTK+ and GPLv3, and is available here: https://github.com/unwind/freemon. It's really handy when doing "bare-metal" development on the Freedom board.

Get yourself a discovery board from ST, same architecture (actually: a good range of choice) and no need to solder a 3 mm2 BGA ;)

The discovery boards are absolutely awesome and very cheap. I highly recommend them as well!

There is also a fantastic RTOS called ChibiOS that has a focus on the STM32 chips and has great support.

ChibiOS seems to work OK for me, though I haven't fully tested it yet. I'm running a port on both the M4 and M0 cores of an LPC4357, the 204mHz part. It's pretty quick.

I'd love to have 100 of them! It probably wouldn't be $0.75/ea for only 100, probably closer to $1.00 each, but still. $100 for 100 MCUs to throw into projects would be awesome. 48Mhz is a lot of hertz to throw at a lot of problems.

Hell, at that price, you can afford to do stupid shit with them, like put them in your friends' LED lightbulbs to screw with them, or build a physical neural-network computer, just so you can hook up LEDs between all the interconnects and make a blinklichten display.

The only problem is that they are ball grid array devices. I wouldn't necessarily say that BGA is impossible for a hobbiest, but typically you're just not going to find that kind of equipment at your local hackerspace.

The listed price is $0.75/ea for 100,000 so at 100 it would probably be around $2-3/chip. Still pretty darn cheap for what it can do!

Though, if the goal is to have a really cheap, programmable chip that doesn't consume a lot of power, then the MSP430 is probably a better bet. 16MHz MCU with admittedly very little memory of its own for about $0.35/ea for a thousand.

In some ways BGA is even easier, aiming a hot air gun requires less general accuracy than a fine soldering iron tip. The only difficult part is the size of the things.

Freescale will probably do a Freedom Board with one of these on it, I expect it to sell for ~$13.

Not the chip in the article, but still a Cortex M0+ http://www.nxp.com/products/microcontrollers/cortex_m0_m0/lp... These are about £0.71 at single unit quantities and are very hobbyist friendly in a DIP package. Not sure what I will do with them, but I feel the need to buy 100.

Yep, I keep trying to find an excuse to use then, largely though I end up wanting more IO than you usually find in the DIP ARM packages. With a controller as tiny as those in the article, it should be possible to turn it into a 14/16 pin DIP-like; I'm assuming that you could throw an XTAL on the adapter board, or that you can reduce the pins further since there's likely more than one ground and vcc. It would certainly be a nice toy to play with for projects since I usually don't need more than 10 i/o and if I do, i can get away with shift registers when I need more.

Note that as far as I know MCUs from that series don't have an ADC, which can be a real PITA.

Personally, I've switched to using MCUs in QFP packages a while ago. You get a lot more pins, peripherals, speed, etc for the physical dimensions and price. If you decide to make a custom PCB for a project you don't end up stuck with a huge DIP package or having to evaluate and port the software to a new MCU in an SMD package.

QFPs are perfectly easy to hand solder with the right tools, which are in fact really basic: either a temperature controlled soldering station or a hot air station and solder paste.

I'm now experimenting with QFN packages, which reduce cost and size compared to QFP. Hand soldering seems to work ok, but I have yet to see the yield for small batch manual assembly.

We've worked with an assembly house that does manual assembly for small-quantity (10-20) batches. Usually they ask for extras due to attrition, but so far we've not lost any.

I usually check the quality of their assembly under a 20x microscope. I've only found 1 board that had a bit of stray solder between 2 pins which was easy to clean. So, yes, manual assembly seems to work, but that may depend on the assembler proficiency.

This page: http://www.freescale.com/webapp/sps/site/prod_summary.jsp?co... says "10000 @ US$1.03 each". Not too bad. Not a very hobbyist-friendly form factor, though.

I'm currently playing with a TI Tiva-C development board, and it's great.

http://www.ti.com/ww/en/launchpad/launchpads-tivac-ek-tm4c12...

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