ESP8266 Community Forum

- Mon May 02, 2016 9:48 am #46695 Hi,

I have a project in mind that includes reading RS232 signals through an audio jack. Is that possible? Maybe through UART?
Are there any libraries? And how do I connect it?

I have searched a lot, but couldn't find rarely any information.

Thanks!

- Mon May 02, 2016 12:24 pm #46710 Hi,

This sounds like you are using an audio jack to physically connect the Tx and Rx lines of the serial connection .

Thanks Stuart

- Mon May 02, 2016 12:45 pm #46712 Audio Jack of what ? on a PC ?

Beware that all audio jack are AC coupled, so there is no way to distinguish between HIGH and LOW of digital signals.
So, trying to decipher a UART signal is not possible.

Also, beware that RS-232 signal is not a plain TTL UART, the RS-232 signal swings between higher voltage, usually around +/- 7V and is inverted compared to TTL-levels.