Introduction

The FreescaleMC68HC05P1A microcontroller unit (MCU) is pin compatible with the MC68HC05P1 with port and interrupt enhancements available. This device is available in a 28-pin dual in-line

package (DIP) or a small outline integrated circuit (SOIC) package. A functional block diagram of the MC68HC05P1A is shown inFigure 1-1.

Features

Features of the MC68HC05P1A include:

? Low-Cost, M68HC05 Core

? 28-Pin Dual In-Line Package (DIP) or Small Outline Integrated Circuit (SOIC) Package

? On-Chip Crystal/Ceramic Resonator or RC Oscillator (Mask Option)

? 2320 Bytes of User Read-Only Memory (ROM) Including:

– 48 Bytes of Page-Zero ROM

– 16 Bytes of User Vectors

? 128 Bytes of On-Chip Random Access Memory (RAM)

? 16-Bit Timer with Output Compare and Input Capture

? Edge/Level-Sensitive Interrupt or Edge-Sensitive Only (Mask Option)

? Computer Operating Properly (COP) Watchdog Timer

? 20 Bidirectional Input/Output (I/O) Lines and One Input-Only Line Including:

– Individual Mask Selectable Pullups/Interrupts on Port A Pins

– High Current Sink and Source on Two I/O Pins (PC0 and PC1)

? Single-Chip Mode

? Power-Saving Stop and Wait Modes

? Stop Conversion to Halt Mode (Mask Option)