Serial network device driver

The Serial network device driver uses a couple of environment variables. These are

• SERNET.NODE Node number. Can be 1-64.
• SERNET.PORT. Communication port number
• SERNET.IRQ. Communication port IRQ number
• SERNET.BAUDRATE. Communication port baudrate. Can be 2400-115000 baud

The driver works in at least 57600 baud with Pentium 300, and 19200 with a 386SX-16. It also supports controlling carrier with RTS on RS485 networks.

The protocol is described in detail here