**The MCF51EM256/128 series microcontrollers are a member of the

ColdFire® family of reduced instruction set computing (RISC) microprocessors.**

This document provides an overview of these 32-bit microcontrollers, focusing on their highly integrated and diverse feature set.
These microcontrollers are systems-on-chips (SoCs) that are based on the V1 ColdFire core and the following features:

**• Operating at processor core speeds up to 50.33 MHz (peripherals

operate at half of this speed) at 3.6 V to 2.5 V and 20 MHz at 2.5 V to 1.8 V**

• Up to 256 KB of flash memory
• Up to 16 KB of RAM
• Less than 1.3 μA of typical power consumption in battery mode, with MCU supply off
• Ultra-low power independent RTC with calendar features, separate time base, power domain, and 32 bytes of RAM
• A collection of communications peripherals, including UART, IIC and SPI
• Integrated 16-bit SAR analog-to-digital converter
• Programmable delay block (PDB)
• Two analog comparators with selectable interrupt (PRACMP)
• LCD driver
• Three serial communications interface modules (SCI)
• Three serial peripheral interfaces
• Inter-integrated circuit (IIC)
• Two 8-bit and one 16-bit modulo timers (MTIM)
• Two-channel timer/PWM module (TPM)