They used the webaudio API to send serial data to a remote Arduino. The hack uses a FET, a capacitor, and a few resistors. They didn’t quite build a real modem with the audio. Instead ...

The serial device 24C256 present on the bus is considered slave, accepting or sending data in response to orders from the ... We can ignore the LSB of the device address while writing the code as the ...

After some research, it was determined that it would be relatively simple to have an Arduino convert incoming serial data into a parallel ... or Clear to Send pin, on the serial side of things.

This tutorial assumes that you have some basic electronics experience, can experiment with Arduino, and have some basic programming skills. Serial Plotter is an amazing tool available in Arduino IDE ...