MC68SC302 PRODUCT INFORMATION

stored in a parallel EEPROM on the external PCMCIA bus. An additional chip select is provided to support

access to an external device from the PC Card interface.

The MC68SC302 also has up to 12 general purpose I/O pins to connect to external circuits. Five external chip

interrupts can be brought in and routed through a built-in interrupt controller to any one of 11 ISA interrupts (or

to the PC Card interface interrupt). The MC68SC302 can be clocked at the same rate as the physical layer

transceiver clock which eliminates the need for a dedicated oscillator or crystal.

Figure 1. MC68SC302 Block Diagram

REFERENCE DESIGNS

Figure 2 shows the 68SC302 in an NT1 terminal adaptor (TA) application using the MC68SC302. The TA

supports a basic rate interface (BRI). The 68SC302 is connected gluelessly to the ISA bus connector and

performs the Plug and Play interface using the serial EEPROM for storage of non-volatile Plug and Play data.

Data and control accesses from the PC to the MC68SC302 can be selectively memory or I/O mapped. Only

one clock source (crystal or oscillator) is needed for a simple terminal adaptor.

1536 BYTE

RAM

SCC1

2 SMCs

SCP

IDL/GCI INTERFACE

COMMUNICATIONS

PROCESSOR

ISA PnP/

PCMCIA

INTERFACE

IDL/GCI PINS

ISA PnP

INTERFACE

PCMCIA

INTERFACE

NMSI I/F

NMSI PINS

PIO AND INT I/F

PIO AND INTERRUPT PINS

SCC2

SCC3

Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com