Yes, BrightSign units that have a serial port support sending and receiving bytes, in addition to strings.
When sending or receiving bytes, you must use decimal values. Many websites have tools for converting between decimal, hex, and ASCII values:
You can also use a standard Windows calculator to convert between hex and decimal. To do so, open the calculator, go to View and select Programmer mode.
To send bytes from a BrightSign player over the serial port, you need to use the Send - Serial byte or Send - Serial bytes (comma separated) commands in BrightAuthor:connected (you can also use a custom script). This is the same option you would use for sending Hex or Binary values.
In BrightAuthor:connected, you must select an Interactive playlist and use the commands (available under the Advanced tab of a state or event) to send a byte or bytes. The serial Protocol should be set to ASCII mode under the Presentation Settings > Interactive > Connectors tab in a presentation.
You can also receive bytes by setting the serial Protocol to Binary mode in Presentation Settings > Interactive > Connectors in a presentation.
You can then use Serial Input events to trigger transitions and other events in an Interactive playlist. Separate the serial values with a comma within the Specify Serial Input field, for example, "31 0D" in hex would be "49,13" in decimal.