I recently picked up my Photon and played around with it using the Sparkfun Micro OLED screen. I am still amazed by the nice browser-based editor and the OTA updates; and how quickly it was possible to get code running.
I really like EPDs, the company I am working for (Plastic Logic) actually manufactures eInk-based ePaper displays (roughly compareable to the one used in the Kindle). Generally the advantage of ePaper displays is that they can keep their image content visible even when the MCU is powered of, which can be pretty nice for power-limited, e.g. battery driven projects. If your project demands rather static image content, changing only a daily, hourly or minutely basis, then you just need some milliamps to change the image content itself, thats it!
So I tried to control one of these displays via the Photon. First on the breadboard, then via PCB. It now works fine, you can see a short demo here:
To address the display I used @peekay123’s nice GFX-library and modified it slightly to work with the controller used in the EPD. It now roughly supports standard and fast updates, automatic temperature dependent waveform selection, fonts and some gfx stuff.
I am now thinking if I should continue this project and if so how to proceed. Experimentally I further tested a small accelerometer which adds a simple touch simulation to the EPD shield. By tapping or double-tapping on the screen you could start/stopp events or wake-up the Photon from deep sleep. This could also be useful for portrait/landscape detection.
So a wild idea would be to develop now a new shield with an 1.1" ePaper display for the Photon as a plug and play solution. From the outline it could look roughly compareable to the Sparkfun Mirco OLED shield. The resolution of the display would be a bit higher, enough to display e.g. the system status, timestamps, short messages, twitter tweets etc.
As a general question, are there be more people interested in such an 1.1" ePaper shield for the PhotonElectron/Bluz? Or are there already other screen shields available besides the oled shield from sparkfun? I have seen some tinkering solutions around repaper.org but so far no really nice plug and play solution yet?! I would really like to realise a project like this but would be interested in your feedback first before spending too much time on it.
Please let me know your comments. Thanks!
). I could try to test this once I am back from holiday…
). The power consumption of the shown display is roughly 5mA@3.3V for the duration of an image update (typically~0.6s). The value also depends to some extend on the image content. Larger displays will draw more power. PL manufactures displays between 1.1" and 15.4". Most of these designs are unfortunately customer-specific and not freely available. With the size the price and complexity increases significantly… Thatswhy I would prefer to start with a small display first.
