S12A Automotive and Industrial Microcontrollers (MCUs)

Block Diagram

S12A Microcontroller Block Diagram

S12A Microcontroller Block Diagram


  • 16-bit HCS12 CPU
  • Upward compatible with M68HC11 instruction set
  • Interrupt stacking and programmer's model identical to M68HC11
  • Instruction pipe
  • Enhanced indexed addressing
  • Multiplexed external bus
  • Memory
  • 512 KB flash EEPROM
  • 14 KB RAM
  • Two asynchronous serial communications interfaces (SCI)
  • Three serial peripheral interfaces (SPI)
  • Two 8-channel ADCs
  • 8-channel pulse-width modulator (PWM)
  • 29 discrete digital I/O channels (Port A, Port B, Port K and Port E)
  • 20 discrete digital I/O lines with interrupt and wake-up capability
  • Inter-IC Bus
  • 10-bit resolution
  • Software-compatible modules

Part numbers include: MC9S12A128CFUE, MC9S12A128CPVE, MC9S12A256CFUE, MC9S12A256CPVE, MC9S12A256MPVE, MC9S12A256VPVE, MC9S12A32CFUE, MC9S12A512CPVE, MC9S12A64CFUE, MC9S12A64CPVE.


Quick reference to our documentation types.

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4 hardware offerings


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Note: For better experience, software downloads are recommended on desktop.

Engineering Services

5 engineering services

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