NXP Semiconductors MC68EC000EI16R2

Overview

MC68EC000EI16R2 from Motorola is a 16-/32-bit embedded controller CPU implementing the M68000 instruction set architecture, featuring a 16-bit external data bus, 24-bit address bus (16 MB address space), and no on-chip MMU or FPU. It operates at 16 MHz, uses CMOS technology, and targets cost-sensitive industrial control and legacy embedded systems requiring binary compatibility with MC68000 software.

For engineers reviewing the MC68EC000EI16R2 datasheet, MC68EC000EI16R2 pinout, MC68EC000EI16R2 application, or MC68EC000EI16R2 equivalent, key selection considerations include its 16 MHz maximum clock frequency, absence of memory management unit, lack of floating-point unit, 68-pin PGA package, and software compatibility with the full M68000 family instruction set.

Technical Context

The MC68EC000EI16R2 implements the same integer instruction set and programmer's model as the MC68000, including eight 32-bit data registers (D0–D7), eight 32-bit address registers (A0–A7), a 32-bit program counter, and a 16-bit status register with condition codes. Its internal 32-bit ALU and registers support full 32-bit operations, while external interface is limited to 16-bit data transfers and 24-bit addressing.

It executes instructions in a three-stage pipeline (fetch, decode, execute) and supports all standard M68000 addressing modes-including register direct, absolute short/long, immediate, and various indexed and indirect forms-but omits virtual memory features present in MC68010+ derivatives. Exception handling follows the M68000 vector table layout with 256-byte spacing.

Key Specifications

Pinout & Package

MC68EC000EI16R2 is housed in a 68-pin ceramic pin grid array (PGA) package with 0.1-inch pin spacing, designed for through-hole mounting and high-reliability industrial applications. Pin functions follow the standard MC68000 pinout with adaptations for embedded use, including dedicated bus arbitration and reset signaling.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar embedded controller applications.

Compared with MC68EC000EI16R2, the FN16R2 offers identical functionality in a lower-cost PLCC package suited for reflow assembly, while the MC68330 provides modern peripheral integration at the expense of software compatibility and increased design validation scope.

Availability

MC68EC000EI16R2 is available at Aetrix Electronics and suitable for industrial PLC controllers, legacy medical devices, point-of-sale terminals, and avionics maintenance units requiring stable component supply across extended product lifecycles.

Supply support for MC68EC000EI16R2 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Motorola Semiconductor (now part of NXP Semiconductors) was a pioneering developer of microprocessors and embedded controllers, known for the M68000 family and foundational contributions to embedded computing architecture.

The MC68EC000EI16R2 belongs to Motorola's embedded controller product line, designed specifically for cost-optimized, high-reliability applications where full M68000 software compatibility is essential but MMU/FPU functionality is unnecessary.

FAQ

What is the maximum operating frequency of the MC68EC000EI16R2?

The MC68EC000EI16R2 is rated for a maximum clock frequency of 16 MHz. This specification is guaranteed across the full industrial temperature range (–40°C to +85°C) and under nominal 5 V supply conditions. Operation above this frequency may result in undefined behavior or timing violations, and is not supported by Motorola's characterization data for the MC68EC000EI16R2.

Does the MC68EC000EI16R2 include an on-chip memory management unit (MMU)?

No, the MC68EC000EI16R2 does not include an on-chip MMU. Unlike the MC68010 and later members of the M68000 family, it implements only the base integer instruction set and user/supervisor programming model without virtual memory support. Systems requiring memory protection or paging must implement external MMU logic, such as the MC68851, or operate in flat memory space.

Is the MC68EC000EI16R2 pin-compatible with the original MC68000?

The MC68EC000EI16R2 shares the same 68-pin PGA footprint and signal-level pinout as the MC68000, making it mechanically and electrically pin-compatible in most designs. However, subtle differences exist in bus timing and reset behavior; designers should verify DTACK assertion timing and interrupt acknowledge sequences before direct substitution in legacy MC68000 systems.

What package type is used for the MC68EC000EI16R2?

The MC68EC000EI16R2 is packaged in a 68-pin ceramic pin grid array (PGA) with 0.1-inch pin spacing. This hermetically sealed package provides superior thermal stability, moisture resistance, and mechanical robustness compared to plastic alternatives, aligning with requirements for industrial and aerospace-grade applications.

Can the MC68EC000EI16R2 execute floating-point instructions?

The MC68EC000EI16R2 does not contain an on-chip floating-point unit and cannot natively execute floating-point instructions. It relies on software emulation or external coprocessors like the MC68881 or MC68882. Floating-point opcodes will generate an exception unless intercepted and emulated by host firmware - a capability confirmed in the M68000 Family Programmer's Reference Manual for the MC68EC000EI16R2.