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Comment by siscia | Hacker News Reader

All I am looking for is a couple of devices that you pair together.

The first devices should only be able to read values from some standard input source and transmit them in a secure way to the second device.

The second devices, the receiver, should only be able to receive values from a swarm of transmitter and stream values over via USB.

Those devices should be crazy cheap, actually they do close to nothing, very power efficient, open source and without whistle and bells...

No integrated editor (why do I need an editor anyway), no integrated dashboard or data collect services, that can be easily implemented later...

Is there anything similar ?

Edit: USB, not TCP/UDP

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One of the various esp8266 boards comes to mind. You can find them for a few bucks off ebay with various levels of functionality. They can act as wifi aps, support wpa, and have a few io pins at the very least.

Though one of the things you'll discover with a lot of embedded chips is that the integrated editor they are paired with tend to have utilities to help you manage the IO configuration registers, clock dividers, and other less than and/or non-intuitive parts of development.

There are innumerable ways to do this with traditional embedded software tools, not need for any "IoT" stuff, for example LwIP on any number of supported dev boards.

What people never seem to realise about embedded s/w is that these devices are only cheap (and hence viable as products) when produced in many thousands/millions... Because of this, the bill-of-materials overrides any other concerns so you end up picking the smallest/cheapest possible device you can and do your utmost to make it work.

This means you need to be intimately familiar with the low-level aspects to be able to optimise your code to the hardware. The best you can say about these environments are that they are for "rapid-development". no one would ever take a design created in one of these type of environments (Arduino included) and make a viable product from it unless cost was not an issue, which is never the case in the embedded world.

So, in answer to your question, it is all possible... apart from the 'cheap-as-chips' part unless you opt for traditional low-level embedded s/w design.

Don't quite grasp it, I am not into the field much, but I try my best.

A little chip that can read analogic OR digital IO and securely send over via radio seems to me like a very standard, reusable and useful piece of hardware.

It is something that you can sell to pretty much every industry, so you have a lot of scale to leverage.

I do understand that, if your application need to read temperature and send it over you will design the whole chip together, but when your application need to read also humidity and send it over I believe that you can reuse the design of the old chip; so, over the years, a standard way to read from IO and send over secure radio connection should emerge.

There are standards for each part of that process, both reading the ADC and transmitting data over a low-power WAN.

The problem is that on its own, that isn't a saleable product, everyone who has a need for that would be able to make it cheaper if integrated into their product as-a-whole. Integration is everything.

One question is: can you do it securely on your own ? really ? can you inspire trust with your customers about that ?

Because some markets like the industrial market - will be willing to pay a bit more for that.

I would recommend low power nRF51 chips. It's a Cortex M0 with integrated 2,4GHz radio. You can use is for Bluetooth Low Energy and communicate with other chips / smartphones / etc (manufacturer provides a BLE stack) or your own simple protocol. There are some modules below $10, but those would require additional USB chip (like ft232 or $2 pl2303 / ch341 module).

If you need a long distance (like 1km) communication then you need a "larger" radio which works in ISM band. For the cheapest solution I'd go with mass produced devices - two WiFi APs with 2 directional antennas + some custom boards ob both sides or APs with open firmware like openWRT.

Teensy LC - https://www.pjrc.com/teensy/teensyLC.html

Nice, but don't quite what I was looking for.

The really missing piece is the connectivity, I need something that can read data somehow and then transmit a point A to a point B, where A and B are at least 1km away from each other...

The 1km requirement is the killer for this plan, as you run into radio regulatory requirements. There is the "Weightless" system operating in the old analog TV bands, but I'm not sure that's made it into shipping products yet.

https://en.wikipedia.org/wiki/Weightless_%28wireless_communi...

These aren't crazy cheap but meet all your other requirements: http://flutterwireless.com/

LoRa is a low power,low data rate modulation scheme that can transmit miles. Modules are starting to be available: http://www.microchip.com/design-centers/wireless-connectivit...

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