Chapter 2.System board features

Microphone

for connecting a microphone.
Super input/output controller
Control of the integrated input/output (I/O) and diskette drive controllers is provided by a single module.
This module, which supports Plug and Play, controls the following features:
Diskette drive interface
Serialport
Parallelport
Keyboard and mouse ports
General-purpose I/O ports
Diskette drive interface
The PC 300PL Personal Computer has four drive bays for installing internal devices.The following is a
list of devices that the diskette drive subsystem supports:
1.44 MB, 3.5-inch diskette drive
1.44 MB, 3.5-inch, 3-mode drive for Japan (no BIOS support for 3-mode drive)
1.2 MB, 5.25-inch diskette drive
1 Mbps, 500-Kbps, or 250 Kbps internal tape drive
One connector is provided on the system board for diskette drive support.For information on the
connector pin assignments, see “Diskette drive connector” on page31.
Serialports
Two universal asynchronous receiver/transmitter (UART) serial ports are integrated into the system
board.The serial ports include 16-byte data, first-in first-out (FIFO) buffers and have programmable baud
rate generators.The serial ports are NS16450 and PC16550A compatible.
For information on the connector pin assignments, see “Serial port connector” on page34.
Note: Current loop interface is not supported.
The following figure shows the serial port assignments in the configuration.
The default setting for the serial port is COM1.
Parallelport
Integrated in the system board is support for extended capabilities port (ECP), enhanced parallel port
(EPP), and standard parallel port (SPP) modes.The modes of operation are selected through the
Configuration/Setup Utility program with the default mode set to SPP.The ECP and EPP modes are
compliant with IEEE 1284.
The following figure shows the parallel port assignments used in the configuration.
Figure 4. Serial port assignments
Port assignment Address range (hex) IRQ level
Serial 1 03F8–03FF IRQ4
Serial 2 02F8–02FF IRQ3
Serial 3 03E8–03FF IRQ4
Serial 4 02E8–02FF IRQ3
10Technical Information Manual