A developer found an old Beetel M59 landline telephone while cleaning and turned it into a Spotify controller. By reverse-engineering the keypad matrix with a multimeter, wiring the handset hook switch, replacing the original display with a 16x2 I2C LCD, and using an ESP32 paired with a backend that maps dial codes to Spotify URIs, dialing a number on the phone now triggers playback of a specific track or playlist. The ESP32 caches song mappings on boot to minimize API calls, and the hook switch triggers pause/resume. The project repo is publicly available.
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okay but what's inside a telephone?reverse engineering (aka poking random pins until something makes sense)the idea didn't come from the phonewhat if i could dial a number and it plays a songhardware hacking beginsthe lcd had to gonow the actual systemhow dialing actually worksexamplecontrolsone important design decisionthe moment it workedalsoanywaySort: