Ampro Corporation 486E - Manual (Page 95)

Product Reference
2–79
Serial Port
Use SETUP to independently enable or disable either of the two onboard serial ports. When SETUP
is used to enable or disable a port, the change does not take effect until the system is rebooted.
The I/O addresses and interrupt assignments (IRQs) for the serial ports cannot be changed. Table
2–54 lists the I/O addresses and IRQs of each port. These resources are freed for use by other
peripherals installed on the PC/104 bus when their respective ports are disabled.
Table 2–54. Serial Port Resources
Port Address
Serial 1 3F8h – 3FFh
Serial 2 2F8h – 2FFh
Serial 3 3E8h – 3EFh
Serial 4 2E8h – 2EFh
The BIOS normally logs Serial 1 and Serial 2 as COM1 and COM2. COM1 and COM2 are logical
designations, not physical values. When the system boots, the BIOS scans the standard serial port
addresses and installs the first port it finds as COM1. If it finds a second port, it installs that one
as COM2, and so on. If you disable a serial port, the designations of all higher-numbered COM
ports changes. See the Serial Port section of this Chapter for more information.
Parallel Port
The Little Board/486e parallel port SETUP allows it to be enabled as the primary or secondary
port. The I/O ports and interrupt request channels are freed for use by other peripherals installed
on the PC/104 bus when the parallel port is disabled. Table 2–55 summarizes the resources that
can be used for the parallel port.
Table 2–55. Parallel Port Resources
Selection I/O Address Interrupt
Primary 0378h - 037Fh IRQ7
Secondary 0278h - 027Fh IRQ5
Disable None None
The BIOS normally logs the primary and secondary parallel ports as LPT1 and LPT2. LPT1 and
LPT2 are logical designations, not physical values. When the system boots, the BIOS scans the
standard parallel port addresses and installs the first port it finds as LPT1. If it finds a second
port, it installs that one as LPT2, and so on. If a parallel port is disabled, the designation of all
higher-numbered LPT ports change.
For further information about utilizing the parallel port, see the section on the bi-directional
Parallel Port.