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Comment by ascorbic | Hacker News Reader

This is nice, but aside from the breadboard-friendly package I'm not sure if it offers any advantage over all of the other nRF51822 modules that are available. Seeed offer one with the same SoC for $7.50, and it's not that hard to solder the package.

http://www.seeedstudio.com/depot/MDBT40P%C2%A0%C2%A0nRF51822...

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Yea this board in no way should cost $25, and is really late to the game with a nordic BLE board. Their website is really disingenuous about things that the Nordic BLE chip just has inside. http://oshchip.org/ Things like: "OSHChip_V1.0 is a unique combination of" (insert list of things inside the nrf51 series). How is it a unique combination of those things?? "You get to be a chip designer." Um, what how exactly do you get to be a chip designer?? You mean, you get to choose whether or not to use the I2C port that is built-in? Anyway, obviously they are marketing this toward students with that type of language. Which is great, good on them, but if it hits hacker news I think it deserves a bit of criticism if they list "professionals" as one of the people this applies to--especially with the price compared to other modules that have been around for some time.

And in the least elegant, but cheapest, form factor WaveShare make a module they call the Core51822[1] that is cloned by tons of folks and is basically the generic nrf51822 module you'll find for ~$5 on ebay. It's the most awkward compromise of 2mm pins (and in double rows too) that make it wholly incompatible with a breadboard yet it's also bigger than any other "embedded" module. But there's also a BLE400[2] "motherboard" which breaks the module's pins out to 2.54mm-spaced connectors, along with a few LEDs and buttons and a USB serial chip (all of which can be disconnected via jumpers), and one of those old, giant, 20-pin JTAG connectors.

It's not able to plug straight into a breadboard, but it does allow full access to every possible IO pin on the chip, and it's probably the cheapest setup you can find. A combination of a Core51822 and BLE400 seem to be easily available for ~$15-$20 shipped, there's even stock available through an Amazon Prime seller for $22.

If you do go for cheaper options, keep the chip differences in mind. The nRF51822 is currently available in three variants, and the differences are big. AA has 16K RAM and 128K Flash, AB has 16K RAM and 256K Flash, and the AC has 32K RAM and 256K Flash. The AC variant was only introduced recently, so some options might still have the older/cheaper variants. But some examples and tools (such as Nordic's BLE sniffer firmware and tools) are starting to require the latest chip with the 32K of RAM, so make sure whatever you're buying explicitly promises you'll get the 32K RAM chip (the AC variant), like this OSHChip does.

[1]: http://www.waveshare.com/wiki/Core51822

[2]: http://www.waveshare.com/wiki/BLE400

Yes, in addition to that there is also:

* RFduino - has the advantage of being available on RS. Downsides: 16 kB version, no 32 kHz crystal, very few IO pins exposed.

* BMD-200 - 32 kB version, cheap if you're in the US, well made, 15 GPIOs exposed, no 32 kHz crystal

* Simblee (by same guys as RFduino) - 32 kB version, 32 kHz crystal, more GPIOs, tiny, quite expensive though

Nordic maintains a list of modules:

https://www.nordicsemi.com/Products/3rd-Party-Bluetooth-Smar...

Here are some more nRF51822 modules that are breadboard-friendly, from Adafruit and Sparkfun. They're just the ones I found from 5 mins searching:

https://www.sparkfun.com/products/13729

https://www.adafruit.com/products/2479

https://www.adafruit.com/product/2633

Not to mention the teensy line. Unless you *really need the slightly smaller size, these things are great:

https://www.pjrc.com/teensy/

Just to be explicit, while this competes in the "tiny but breadboard-friendly microcontroller" market, it's not a nRF51 board (it's actually a more powerful chip, CPU-wise) and it does not have any sort of radio, bluetooth or otherwise.

The support from PJRC is great, though. And if you want to use the Arduino environment, I don't think anyone puts more work into making it work flawlessly on a non-AVR platform than Paul does, not even the Arduino guys themselves with their own ARM boards.

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