Which STM32 board?

[dannyf]

It has less to do with the number of pins: nxp did a great job actually implementing assignable pins on those chips.

It has more to do with the (highly) limited flash and upward mobility. You are not going to code those chips in assembly. Once you start with C, the overhead will be significant for such a small chip. Not to mention that those chips aren't going to hold a lot of instructions to begin with.

[SolarSunrise]

I highly recommend the STM32F4Discovery board. It contains a accelerometer, LED's, a button, a DAC, a digital mic, a headphone jack, and a built in programmer. That certainly will keep you busy for a while.

If you can't buy them cause the shipping is too damn expensive, check out Farnell - Farnell is great and the shipping isn't that expensive either (stuff there is little more expensive then Mouser or Digikey but hey it's in Europe)

Check here:
http://uk.farnell.com/jsp/search/browse.jsp?N=2031+203908&Ntk=gensearch&Ntt=stm32+discovery&Ntx=mode+matchallpartial

STM32F4Discovery:
http://uk.farnell.com/stmicroelectronics/stm32f4discovery/stm32f407-usb-otg-discovery-kit/dp/2009276

FYI, this book by Joseph Yiu is awesome and really helpful. It saved me bunch of times. Here's the UK amazon link:
http://www.amazon.co.uk/Definitive-Cortex%C2%AE-M3-Cortex%C2%AE-M4-Processors-Edition/dp/0124080820/ref=dp_ob_title_bk

EDIT: Just realized gmb42 already told you about Farnell. Oh well.

[Harvs]

RE dealing with packages.  The reality is the Disco boards are so close to the cost of the main chip itself you can just use the whole board instead if size isn't an issue.  Treat it as a module.  You can just rip the other chips off with a hot air tool if you don't want them (e.g. the DAC, accelerometer etc.)  However, if you've got a project that can actually use those, the disco board just got cheaper than buying the chips individually (i.e. F407 board $18.69AUD, the main IC is ~$14.50 + $7.50 for the Accelerometer etc.)

On two projects now which were one offs (i.e. <10), and the emphasis was 100% on getting it done ASAP I've drop the whole discovery board onto the finished product.

I know some will cringe at this, and a year ago I probably would have to.  But the reality is it's worked very well in these niche applications.

[Bored@Work]

The reality is the Disco boards are so close to the cost of the main chip itself you can just use the whole board instead if size isn't an issue.

ST tries to prevent this by trying to force a ridiculous license, yes, a license, on you.

http://www.st.com/st-web-ui/static/active/en/resource/legal/legal_agreement/license_agreement/EvaluationProductLicenseAgreement.pdf

While I personally think ST can stick this license to where the sun never shines and that any sane judge will show ST the door, it might deter a some people from using the boards in products.

[Harvs]

The reality is the Disco boards are so close to the cost of the main chip itself you can just use the whole board instead if size isn't an issue.

ST tries to prevent this by trying to force a ridiculous license, yes, a license, on you.

http://www.st.com/st-web-ui/static/active/en/resource/legal/legal_agreement/license_agreement/EvaluationProductLicenseAgreement.pdf

While I personally think ST can stick this license to where the sun never shines and that any sane judge will show ST the door, it might deter a some people from using the boards in products.

Wow, what an absolute load of bollocks.  According to that licence we shouldn't be using any part of their demo software either (i.e. their examples of how to use the libraries.)  Doesn't matter for me, this is only for very small one off things with practically no commercial value attached to them.

[andersm]

Wow, what an absolute load of bollocks.  According to that licence we shouldn't be using any part of their demo software either (i.e. their examples of how to use the libraries.)  Doesn't matter for me, this is only for very small one off things with practically no commercial value attached to them.

It's a pretty normal CYA license. If you use the board in a product, and it all goes horribly wrong, it's your own fault.

[Harvs]

It's a pretty normal CYA license. If you use the board in a product, and it all goes horribly wrong, it's your own fault.

That's perfectly reasonable, and I never would have expected anything else WRT liability.  But I haven't seen another hardware licence before that restricts you to only using it for self education purposes and nothing else.

[wisementor]

I think this development tool supports some of discovery boards directly and most of STM32 devices. With free version you can utilize up to 25% of device flash memory capacity which could be enough also for medium sized project. Successfully compiled and debugged Chibi/OS and FreeRTOS with it. Includes also project wizard where with few clicks the basic project or example can be created.