Serial port pinout for Brightsign players

The 3.5 mm serial port has the following configuration (from the player's perspective):

Tip: Transmit
Ring: Receive
Sleeve: Ground

Serial Input and Output (Serial Input / Output)

BrightSign players include a UART (asynchronous serial communication) interface. It consists of a 3.5 mm (1/8") connector that connects a serial modem or other devices that use a serial connector, and it uses TTL for communication. The receiver tolerates input voltages between -30V and +30V, with anything below 3V being interpreted as a logic one (1). The transmitter drives +5V for logic zero (0) and 0V for logic one (1).

The default baud rate is 115200, with no parity, 8 data bits and 1 stop bit. These settings can be configured in the software. The serial interface supports TX, RX and ground only - hardware flow control (RTS/CTS) is not supported. The following diagram illustrates the behavior of the TX and RX signals:

The 3.5 mm serial port has the following configuration (from the player's perspective):

Tip: Transmit
Ring: Receive
Sleeve: Ground

A little technical curiosity: It's worth noting that while the manual mentions TTL, the voltage range (-30V to +30V) indicates that the input is quite robust and similar to RS-232 tolerance, even though the actual logic levels being sent out (0V/5V) are pure TTL. Be sure to check that the device you're connecting can handle 5V logic so you don't fry any sensitive equipment!