beautypg.com

I/o subsystem – Texas Instruments EXTENSA 570CD User Manual

Page 43

background image

Priority

Interrupt

Number

Interrupt Source

17

IRQ7

Parallel Port

n

Note: A PCMCIA card can use IRQ 3, 4, 5, 7, 9 and 11 as long as it does not
conflict with the interrupt address of any other device.

4.2.2

I/O Subsystem

The I/O subsystem, implemented with an SMC37C655IR Super I/O
Controller Chip, provides for such functions as internal floppy drive control,
serial and parallel ports and support for the Serial Infrared port. The Super
I/O Controller includes the following features:

100 percent compatible with ISA, EISA, and micro-channel architectures

Built-in floppy disk controller

Two UARTs

Software compatible with the PC16550A and PC16450

MIDI compatible

Infrared support on UART2 (IRDA-compliant)

Bidirectional Parallel Port

Enhanced Parallel Port (EPP) compatible

Extended Capabilities Port (ECP) compatible, including level 2
support

Bidirectional under either software or hardware control

Compatbile with ISA, EISA, and Micro Channel architectures

Ability to multiplex FDC signals on parallel port pins for
external FDD

Includes protection circuit against damage caused when
printer is powered up, or operated at higher voltages

Integral address decoder- provides selection of all primary and
secondary ISA addresses including COM1-4 and LPT1-3.

Enhanced Power Management Function

Enhanced programmable power-down and wake-up modes

Theory of Operation 4-5