General Description
Introduction
The Motorola MC68HC05P18 and MC68HC805P18 microcontrollers (MCU) are members of the M68HC05 Family with:
   • 4-channel, 8-bit analog-to-digital (A/D) converter
   • 16-bit timer with output compare and input capture
   • Serial input/output port (SIOP)
   • Computer operating properly (COP) watchdog timer
   • 21 input/output (I/O) pins (20 bidirectional, one input-only)
  
Features
Features include:
   • Low-cost M68HC05 core running at 2-MHz bus speed
   • 28-pin dual in-line package (DIP) or small outline (SOIC) package
   • 4-MHz on-chip crystal/ceramic resonator oscillator
   • MC68HC05P18:
      – 8064 bytes of user read-only memory (ROM)
      – 48 bytes of page zero ROM
      – 16 bytes of user vectors
   • MC68HC805P18:
      – 8064 bytes of user electrically erasable, programmable read-only memory (EEPROM)
      – 48 bytes of page zero EEPROM
      – 16 bytes of user vectors
   • 192 bytes of on-chip random-access memory (RAM)
   • 128 bytes of EEPROM
   • Low-voltage reset (LVR)
   • 4-channel, 8-bit A/D converter
   • SIOP serial communications port
   • COP watchdog timer with active pulldown on RESET
   • 16-bit timer with output compare and input capture
   • 20 bidirectional I/O lines and one input-only line
   • High current sink and source on two I/O pins (PC0 and PC1)