I'm looking into hacking my digital alarm clock to be able to control it with my Raspberry Pi A+. It has a typical 4 digit screen (7 segment) with two dots in between.
The screen has a brand and printed on it, but no luck finding any information on this Japanese website.
The screen communicates with 14 pins, I have no other information. How would I go about trying to power it and control it through GPIO pins ? Is it feasible?!
Typically, this type of display has a matrix of 7 segment drives x 4 character selects, and probably another pair for the colon; there may well be an am/pm indicator. It can be common anode or common cathode.
You will need a 3V battery & a sensible resistor (320 or thereabouts) or some such to provide around 10mA to an individual LED, and try pins & note which combination lights which segments, + polarity; it soon becomes clear how it's wired. You can then play with drive currents & establish the right resistors (x7) to light it properly.
After that, it's relatively easy!
