Hardware Interrupt; Chapter 4 Page 43 - Brainboxes CC-265 Hardware Manual

PCI Quad RS232 DOS Installation
/H,1 Set handshake 1 for all ports
The /H switches are processed from left to right, so for example
/H,2 /H1,0 /H2,1 would set COM3 to COM16 to handshake mode
2, COM1 to mode 0 and COM2 to mode 1.
The hardware handshakes currently supported are:
Type 0 RS232 DTR/CTS
Type 1 RS422 RTS/CTS
Type 2 RS485 Half duplex
Type 3 RS485 Send only.
Type 4 No handshake used, only TxD, RxD and Gnd need be
connected.

Hardware Interrupt.

Switch: /I n,i
Purpose:
Set interrupt lines for COMn.
'n' specifies the COM port. If n is not specified the interrupt line is
applied to all ports.
'i' is the interrupt line in the range 2 to 7 and 10 to 15 or, to
indicate no interrupt line, -1 or nothing.
For example:
/I1,4 set COM1 to use line 4
/i,-1 sets all ports to no interrupt
/i2, sets COM2 to no interrupt
The /I switches are processed from left to right, so for example
/I,3 /I1,4 sets COM1 to line 4 and COM2 to COM16 to line 3.
A serial port must be assigned an interrupt line before it can be
used. On PC/XT/AT machines and EISA bus machines only one
serial port can use an interrupt line. On PS/2 machines serial ports
can share interrupts. Multiport cards with special interrupt
hardware have different rules- see the information for setting up
those cards.

Chapter 4 Page 43