I am still waiting to get back home to give things a serious try out as
I am on the road still… Another meet up today this time around a
kitchen table with students and several IT teachers and ‘rolled’ my
usual presentation using the WebIOPi digital + Serial interface using
an open wifi LAN out of a recycled router. A demonstration can be set up in minutes. The ability to break out some breadboards with basic digital IO so easily Really does Impress teachers who would normally never touch wires and keep safely to programming. They could all see the level of enrichment and the extra dimension that adding real hardware, models into the real time. It is fun and meaningful for students to work withh. This stuff is now Hot even if most of them had not heard of IoT concepts.
An extra angle close to this simple interface level that I will keep
exploiting is human read-able simple text: Serial or SMS or Twitter.
I think that the ability so send and read meaningful short messages
containing key-words, phrases off a keyboard or phone is a great
feature. Using PIC (picaxe) type systems I find that quite powerful
semi human readable commands can be passed to and from simple u-powered devices. In the case of picaxe it is very easy to Tx and Rx variable data within a single line of PIC.bas type code. It is possible in a
single line command to use a serin delimiter (= keyword) to synch and
crunch variable incoming ascill digital numbers directly into single
bytes and word variables from a free form sentence. A demo I have that handshakes nicely with the serial tab of WebIOPi is a 7 option old school dos type menu that is sent out that a user can remotely respond to. A a range of routines and features deeply embedded at the remote PIC level of a system can thus handshake with human text strings and numbers. There is a level of secuurity here in the simplicity provided a limited range of options are made available.
So my idea is simple: Keep simple serial data available and if SMS /
Twitter type handling can be added and patched to ttyyAMA0 etc on the GPIO. I for one would be keen to use this feature and spread the word and certainly exploit this level of functionality. I have played with twython etc but a more direct type of SMS / Twitter portal somehow into an account Pi I think would be a great feature.
Along this line LoRaWAN ideas ( secure 10km link from a PIC and 3x AA batteries) are now going main stream. LoRa adds 19.5 dB to a radio link budget. The RF Rx works 19.5 dB below the noise floor or against any interfering signals. A typical UART interfaced LoRa radio can connect with 4 jumpers directly TTL Tx, Rx, +3.3 and 0V Again very simple low cost IoT serial over low speed long range radio directly off the Pi GPIO.
Sorry of there are too many ideas in this. I can split them out and provide data, specs and practical information for those wanting to have a play.