APPENDIX I
CONCURRENT DOS CONFIGURATION
MULTI - USER DOS CONFIGURATION

Set I/O port address to 280, interrupt to IRQ3 and interrupt vector to 270H. To install device drivers,  please run the SETUP program, then follow the menu instructions to set up I/O port address, communication parameters (such as: baud rate, parity, data bits, ... etc.), and handshaking.  The hardware configuration is shown below:

For multi-user DOS (Dr. DOS) configuration, set I/O port address to 280H, and interrupt vector to 270H. Any interrupt (IRQ3 to IRQ15) is used.