NXP Semiconductors MC68EN360RC25L

Overview

MC68EN360RC25L from Freescale Semiconductor is a quad integrated communications controller (QUICC) featuring a 32-bit CPU32+ core, dual-ported RAM, and an autonomous Communications Processor Module (CPM) with four serial channels (SCC/SMC), supporting HDLC, SDLC, UART, and BISYNC protocols. It operates at 25 MHz, integrates system integration logic (SIM60), and targets embedded telecom and industrial control applications requiring deterministic real-time communication offload.

For engineers reviewing the MC68EN360RC25L datasheet, MC68EN360RC25L pinout, MC68EN360RC25L application, or MC68EN360RC25L equivalent, key selection criteria include CPM-based protocol acceleration, 25 MHz system clock support, 144-pin PGA package compatibility, and legacy M68000-family instruction set compliance for migration from MC68302 designs.

Technical Context

The MC68EN360RC25L implements a tightly coupled dual-processor architecture: the CPU32+ executes host control code while the CPM independently handles serial I/O using microcoded RISC firmware loaded into on-chip dual-port RAM. Its SIM60 provides memory management, interrupt control, chip select decoding, and bus arbitration - all synchronized to a single 25 MHz system clock derived from an external crystal (EXTAL/XTAL).

Communication peripherals include four SCCs (Serial Communication Controllers) and two SMCs (Serial Management Controllers), each configurable for synchronous/asynchronous operation, with dedicated DMA channels and programmable baud rate generators. The device supports glueless interfacing to DRAM, SRAM, and peripheral chips via its 32-bit multiplexed address/data bus and full IEEE 1149.1 JTAG test access port.

Key Specifications

Pinout & Package

MC68EN360RC25L is housed in a 144-pin ceramic Pin Grid Array (PGA) package with 1.27 mm pitch, designed for high-reliability industrial and telecom applications. Thermal and mechanical specifications are defined in Freescale document MC68360/D.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC68360RC25L, the MC68EN360RC25L adds extended temperature qualification and enhanced burn-in screening, making it suitable for harsh environments; versus MPC860TBCZQ50D, it retains M68k toolchain continuity and lower power at 25 MHz but lacks PCI and cache - critical for legacy migration paths where software reuse and thermal constraints dominate.

Availability

MC68EN360RC25L is available at Aetrix Electronics and suitable for industrial protocol gateways, legacy telecom terminal replacements, secure SCADA RTUs, ruggedized serial routers, and embedded communications infrastructure requiring stable component supply across long product lifecycles.

Supply support for MC68EN360RC25L 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

Freescale Semiconductor (now part of NXP Semiconductors) was a leading designer of embedded processors and analog/mixed-signal ICs, specializing in automotive, industrial, and networking solutions before its 2015 acquisition.

The MC68EN360RC25L belongs to the QUICC family - engineered specifically to offload serial communications processing from host CPUs in mission-critical infrastructure, enabling deterministic real-time performance in telecom access equipment and industrial control systems.

FAQ

What is the primary function of the CPM in the MC68EN360RC25L?

The Communications Processor Module (CPM) in the MC68EN360RC25L is a dedicated RISC co-processor that autonomously handles serial communications tasks including HDLC/SDLC framing, CRC calculation, bit stuffing, and DMA transfers - freeing the CPU32+ core for application-level processing. This architecture ensures deterministic latency for time-critical protocols and reduces overall system interrupt load. The CPM executes microcode stored in the on-chip dual-port RAM, and its operation is fully configurable via dedicated CPM registers mapped in the MC68EN360RC25L memory space.

Does the MC68EN360RC25L support JTAG debugging?

Yes, the MC68EN360RC25L includes a fully compliant IEEE 1149.1 Test Access Port (TAP) controller with TRST, TCK, TMS, TDI, and TDO pins. This enables boundary-scan testing, in-circuit emulation, non-intrusive firmware loading, and real-time debugging without halting CPU32+ execution. The TAP is integrated into the SIM60 module and supports both instruction and data register scans per the JTAG standard. Debug capabilities are documented in Section 8 of the MC68360 User's Manual and require compatible JTAG probes such as P&E Multilink or Lauterbach TRACE32.

What package type and pin count does the MC68EN360RC25L use?

The MC68EN360RC25L uses a 144-pin ceramic Pin Grid Array (PGA) package with 1.27 mm pitch, as specified in Freescale document MC68360/D. This PGA variant provides superior thermal dissipation and mechanical stability compared to plastic QFP alternatives, making it suitable for extended-temperature industrial applications. Pin assignments - including multiplexed address/data bus, chip selects, serial I/O, clock, and JTAG signals - are fully detailed in Section 2 ("Signal Descriptions") of the MC68360 User's Manual. No lead-free or RoHS-compliant version was released for this specific speed grade.

Can the MC68EN360RC25L replace the MC68302 in existing designs?

Yes, the MC68EN360RC25L is architecturally positioned as an upgrade path from the MC68302, offering enhanced performance, expanded memory mapping, additional serial channels, and improved interrupt handling. Freescale explicitly addresses migration in Section 1.3 of the MC68360 User's Manual, noting hardware compatibility in bus signaling and software compatibility in CPU32+ instruction set (a superset of the MC68302's CPU). However, PCB layout changes are required due to the larger 144-pin PGA footprint and updated signal routing - particularly for the multiplexed address/data bus and CPM-specific control lines.

What is the maximum operating frequency of the MC68EN360RC25L?

The MC68EN360RC25L is rated for a maximum system clock frequency of 25 MHz, as indicated by the "25" suffix in its part number. This frequency applies to the main EXTAL/XTAL input driving the on-chip oscillator, which synchronizes both the CPU32+ core and the CPM. Electrical characteristics in Section 10 of the MC68360 User's Manual confirm timing parameters (e.g., read/write cycle times, setup/hold requirements) are guaranteed only up to 25 MHz. Operation beyond this frequency violates datasheet specifications and may result in metastability or functional failure.