The MC68HC812A4 microcontroller unit (MCU) is a 16-bit device composed of standard on-chip peripheral modules connected by an intermodule bus. Modules include a 16-bit central processing unit (CPU12), a Lite integration module (LIM), two asynchronous serial communications interfaces (SCI0 and SCI1), a serial peripheral interface (SPI), a timer and pulse accumulation module, an 8-bit analog-to-digital converter (ATD), 1-Kbyte RAM, and memory expansion logic with chip selects, key wakeup ports, and a phase-locked loop (PLL).

• Low-Power, High-Speed M68HC12 CPU
• Power Saving STOP and WAIT Modes
• Memory
  • 1024-Byte RAM
  • 4096-Byte Electrically Erasable Programmable Read-Only Memory (EEPROM)
  • On-Chip Memory Mapping Allows Expansion to over 5-Mbyte Address Space
• Single-Wire Background Debug Mode
• Non-Multiplexed Address and Data Buses
• Seven Programmable Chip Selects with Clock Stretching (Expanded Modes)
• 8-Channel, Enhanced 16-Bit Timer with Programmable Prescaler
  • All Channels Configurable as Input Capture or Output Compare
  • Flexible Choice of Clock Source
• 16-Bit Pulse Accumulator
• Real-Time Interrupt Circuit
• Computer Operating Properly (COP) Watchdog
• Clock Monitor
• Phase-Locked Loop
• Two Enhanced Asynchronous Non-Return to Zero (NRZ) Serial Communication Interfaces (SCI)
• Enhanced Synchronous Serial Peripheral Interface (SPI)
• 8-Channel, 8-Bit Analog-to-Digital Converter (ATD)
• Up to 24 Key Wakeup Lines with Interrupt Capability
• Available in 112-Pin Thin Quad Flat Pack (TQFP) Packaging