ST7565 Negative Graphic LCD running from a Pi/Arduino combo
I've hooked up the beautiful Negative LCD I picked up from HobbyTronics to my new broken-out PiDuino setup.
Whilst I have not yet tweaked the Pi to send anything sane over its serial line ( the serial terminal is still enabled ) I have added a 3.3v voltage regulator to my breakout breadboard, and an Arduino running at 16Mhz/3.3v to drive the ST7565 with a Sketch that accepts messages over serial and displays them with a flashing alert backlight.
The reason for using a voltage regulator circuit is simple; the Pi's 3.3v GPIO pin only supplies 50mA max, and I'm definitely going to exeed that during my tinkering.
The serial terminal lead to some interesting garbage on the LCD. Over the next few days I plan to write a Raspberry Pi counterpart to this setup, delivering notifications with custom backlight colours to match each service. There are a few simple challenges to overcome, including trying to get the brightness of each backlight colour consistent with the others and successfully fading one colour authentically into the other without giving the poor Arduino a floating-point headache.