GENERAL DESCRIPTION

The MC68HC05P9A is a 28-pin device based on the MC68HC05P9. The memory

map includes 2112 bytes of user ROM and 128 bytes of RAM. The MCU has two

8-bit input/output (I/O) ports, A and C. Port B has three I/O pins and port D has

two pins, one that is I/O and the other input only. The MC68HC05P9A includes a

four-channel 8-bit analog-to-digital (A/D) converter, a simple serial I/O peripheral

(SIOP), and an on-chip mask programmable computer operating properly (COP)

watchdog circuit.

Features

• Low Cost

• HC05 Core

• 28-Pin Package

• On-Chip Oscillator with RC or Crystal/Ceramic Resonator Mask Options

• 2112 Bytes of User ROM Including 16 User Vector Locations

• ROM Security Feature

• 128 Bytes of On-Chip RAM

• 16-Bit Timer

• 20 Bidirectional I/O Lines, One Input-Only Line

• Mask Programmable Keyscan (Pullups and Interrupt) on Eight Port Pins

(PA0 through PA7)

• Two Port Pins with High Current Drive Capability (PC0, PC1)

• User Mode

• Four-Channel 8-Bit A/D Converter

• Self-Check Mode

• Power-Saving Stop and Wait Modes

• STOP Conversion to Halt Mode (Mask Option)

• Edge-Sensitive or Edge- and Level-Sensitive Interrupt Trigger Mask

Option

• Simple Serial Input/Output Port

• Mask Option Selectable Watchdog Timer (COP)