driver supports the non-keyboard 8250-like UART connected to the frodo(4)
Apollo utility chip. The first UART is used to communicate with the Domain keyboard. The second is the serial console port when the firmware is in Domain/OS mode, and is mapped to select code 9 by the HP-UX firmware (except on 425e models). As such, the second UART is handled by the dca(4)
driver on all models but the 425e.
There is no tty attached to the first UART as it lacks modem/flow control and is directly connected to the keyboard connector.
Input and output for each line may be set to one of the following baud rates: 50, 75, 110, 134.5, 150, 300, 600, 1200, 1800, 2400, 4800, 9600, 19200, or 38400.