Nope, no microcontroller here, just a full-blown cellphone utilized as the brains of this bit robot. The trick behind exactly how it works is in the seems the phone makes. The touch tones, understood as DTMF, are monitored by the circuit mounted on the front half of the chassis as well as are accountable for driving the motors.
[Achu Wilson] developed the circuit around an MT8870 chip which decodes the DTMF seems as well as utilizes the BCD output to feed some logic chips. A 4 line to 16 line decoder as well as an inverter chip style the signals for utilize as inputs to the L293D motor driver. The video after the break shows him driving the rover directly by pressing number on the phone (like a tethered remote control). however he mentions that it’s possible to phone call the phone as well as press the numbers remotely. We presume you requirement to link the phone call manually as we see no method to automatically answer calls.
This is definitely a fun method to play around with the DTMF protocol.