The MC68HC11EA9 and MC68HC711EA9 microcontroller units (MCUs) are high-performance members of the M68HC11 family of MCUs. The MC68HC(7)11EA9 MCUs have a multiplexed external address and data bus and are characterized by high speed and low power consumption. Their fully static design allows operation at frequencies from 3 MHz to dc. The addition of a phase-locked loop (PLL) frequency synthesizer to the timer circuitry further enhances low-power operation and allows the use of lower frequency crystals while maintaining a clock speed of up to 3 MHz. This document contains information concerning standard and custom-ROM devices. Standard devices are those with ROM or with EPROM replacing ROM (MC68HC711EA9). Custom-ROM devices have a ROM array that is programmed at the factory to customer specifications. Where information in this document refers to both the ROM and EPROM versions, the device is referred to as MC68HC(7)11EA9. 1.1 Features