Since Jolla introduced the Other Half, they were talking about innovation that goes way beyond just a colourful back cover. Now we know that the phone itself will have an I2C port on the back, which has lead to many expectations on the future expandability of Jolla including with electrical devices. Not mentioning that the Other Half will be 3D printable, making it possible to replicate it, moreover this will allow developers and even hobbyist to manufacture they own extension, a functioning Other Half.
Well, I am sure many readers were wandering what I2C means, and what its possibilities are. I2C was designed to allow communication between integrated circuits on a short distance. I2C (prior called as IIC too) translates to “Inter IC“ which describes it well. I2C is used in many hardware, and still very popular. I need to mention TWI as well here, which can be partly or fully compatible with I2C. Microcontroller manufacturers call their own version TWI which translates to Two Wire Interface to avoid trademark conflicts.
The good thing is, I2C (or TWI) was designed nearly 30 years ago, which means it is very well supported by sensor manufacturers for example. What are the advantages of I2C that makes it a perfect decision from Jolla to support it:
-It needs only 2 bus lines
-Relatively high speed communication
-Real multi device support including multi-master
Without going much into electronics, I’d like to show some ideas, give some hints for everyone on the commercially available components that support I2C, mostly sensors.
List of I2C (TWI) devices:
|Temperature sensor||Precision temperature readings|
|EEPROM memory||A few kbytes of storage|
|Humidity sensor||Environmental data acquisition|
|Accelerometer||Accurate motion detection|
|Gyroscope||Accurate motion detection|
|Color sensor||Color measurement|
|Light intensity sensor||Ambient light measurement|
|Proximity sensor||Close range (on the desk) detector|
|Pressure or force sensor||Low weight scale or environmental data|
|Touch sensors||Back touch buttons|
|Microcontroller||Connectiong inputs, outputs, peripherials|
|LED drivers||Controlling multiple light sources|
Microcontrollers are little processors, that could be programmed to many things, most micros have hardware ports for I2C communication, and other ports can be used to connect to other devices.
Size wise, these devices come in really tiny packages, that is still available commercially to everyone, and can be stuffed in a few millimetre width of enclosure, like the Other Half. In theory it would be even possible to build an e-INK display Other Half as well for reading e-books, with the appropriate devices in a few more millimetres, but that is something we should wait for a big manufacturing company to make.
For hobbyists there are still many possibilities.
Keep in mind that the Other Half still must be an attachment to the phone body, and not something that the phone attaches to. I would avoid ideas that would use Jolla as a display for example to a smart beer faucet (unless it is wireless). Whatever is its function, it need to be slim, and simple, something that adds at least one specific function to the smartphone.
Like a game controller, a proximity card reader, a precision light meter for photographers, or a pulse oximeter. I am sure many talents will have great ideas.
We still need to see the connector on the Jolla’s back and learn how to use the port in our software.
Do not forget that a special function Other Half needs someone to writes applications for them too. So I expect small groups of electrical designers and developers who join to work together on their ideas.
I hope this article will help you understand what this I2C expansibility is all about, and I hope more people will turn up with their Other Half ideas.