GENERAL DESCRIPTION

The W78C438C is a high-performance single-chip CMOS 8-bit microcontroller that is a derivative of the W78C58 microcontroller family. The W78C438C is functionally compatible with the W78C32, except that it provides either a 64 KB program/1 MB data memory address or memory-mapped chip select logic, five general I/O ports, and four external interrupts.

FEATURES

• 8-bit CMOS microcontroller

• Fully static design

• DC to 40 MHz operation

• ROM-less operation

• 256-byte on-chip scratchpad RAM

• Either 64 KB program/1 MB data memory address space or 4 memory-mapped chip select pins

• One 8-bit data/address port

• Two 8-bit and one 4-bit (optional) address ports

• Five 8-bit bidirectional I/O ports

- Four 8-bit bit-addressable I/O ports and one 8-bit parallel I/O port

• Eight-source, two-level interrupt capability

• Three 16-bit timer/counters

• Four external interrupts

• One full-duplex serial channel

• Built-in power management

- Idle mode

- Power-down mode

• Packages:

- 84-pin PLCC: W78C438CP-24/40

- 100-pin PQFP: W78C438CF-24/40