outportb(PORT1 + 1 , 0);        /* Turn off interrupts - Port1 */

 oldport1isr = getvect(INTVECT); /* Save old Interrupt Vector for later
					 recovery */

 setvect(INTVECT, PORT1INT);     /* Set Interrupt Vector Entry */
				 /* COM1 - 0x0C */
				 /* COM2 - 0x0B */
				 /* COM3 - 0x0C */
				 /* COM4 - 0x0B */

 /*         PORT 1 - Communication Settings         */

 outportb(PORT1 + 3 , 0x80);  /* SET DLAB ON */
 outportb(PORT1 + 0 , 0x0C);  /* Set Baud rate - Divisor Latch Low Byte */
					/*         0x0C =   9,600 BPS */
					/*         0x18 =   4,800 BPS */
					/*         0x30 =   2,400 BPS */
 outportb(PORT1 + 1 , 0x00);  /* Set Baud rate - Divisor Latch High Byte */
 outportb(PORT1 + 3 , 0x03);  /* 8 Bits, No Parity, 1 Stop Bit */
 outportb(PORT1 + 2 , 0xC7);  /* FIFO Control Register */
 outportb(PORT1 + 4 , 0x0B);  /* Turn on DTR, RTS, and OUT2 */

 outportb(0x21,(inportb(0x21) & 0xEF));  /* Set Programmable Interrupt Controller */
					 /* COM1 (IRQ4) - 0xEF  */
					 /* COM2 (IRQ3) - 0xF7  */
					 /* COM3 (IRQ4) - 0xEF  */
					 /* COM4 (IRQ3) - 0xF7  */

 outportb(PORT1 + 1 , 0x01);  /* Interrupt when data received */