02-07-2020, 12:26 PM
(02-06-2020, 03:51 PM)bcnaz Wrote: Isn't the ear/head phone 'jack' a mechanical switch ?
IE: When you plug in the plug, it opens the speaker circut, and deverts the signal to the plug instead of the speaker ?
No, the headphone, speaker and 'receiver' (the one you hold to your ear when making phone calls) are all separate, and switching is software controlled. The headphone audio goes through a switch chip so that the DIP switch on the back of the phone can switch the socket between headphone and serial interface too. It's on the 'Audio' page of the schematic
