I'm currently looking into getting a sound pin and the most likely candidate right now is the LCD reset pin. Did anyone ever had any problems not using the reset pin of the Nokia LCD? What could I test to make sure it works fine? worst case scenario is turning the lameboy on and off again, I guess. I could try using RX and TX for sound, where depending on the TX state the RX would emit sound (no modem noises while uploading if done right). But if I could free the RST pin for sound, then I could use the same idea for RX and TX to transmit IR maybe. Would be cool features to have, I think.
Also to consider:
- using the D/C pin of the display for other things, maybe move to TX
- auto reset circuit for pin http://www.avrfreaks.net/sites/default/files/SSD1306_OLED_circuit.jpg
- maxim power on reset app note https://www.maximintegrated.com/en/app-notes/index.mvp/id/3227