Intel EE87C196MH: An In-Depth Technical Overview of the 16-Bit Embedded Controller
The Intel EE87C196MH stands as a significant milestone in the evolution of 16-bit embedded controllers, representing a high-performance, highly integrated solution designed for complex real-time control applications. As a member of the acclaimed MCS® 96 family, this microcontroller carved its niche in demanding sectors such as industrial automation, automotive systems, and advanced instrumentation, where processing power, precision, and reliability are paramount.
At the core of the EE87C196MH lies a highly optimized 16-bit CPU with a register-to-register architecture. Unlike traditional accumulator-based designs, this core operates on a 256-byte register file, where any register can function as an accumulator. This drastically reduces bottlenecking and enhances instruction execution speed, enabling the device to handle computationally intensive tasks efficiently. The CPU can perform operations on bits, bytes, words, and even long words (32-bit), providing exceptional flexibility for software development.
A defining feature of this controller is its sophisticated on-chip Peripheral Transaction Server (PTS). The PTS is a dedicated microcoded interrupt handler that functions like a miniature Direct Memory Access (DMA) controller for I/O operations. It significantly reduces the software overhead associated with processing frequent interrupt-driven events—such as those from analog-to-digital converters or high-speed serial ports—by handling data transfers between peripherals and memory independently of the main CPU. This results in faster and more deterministic interrupt response times, a critical requirement in real-time systems.
Memory configuration is another area of strength. The device incorporates a substantial 8 KB of on-chip EPROM (87C196 variant), allowing for the storage of complex control algorithms and firmware directly on the chip, enhancing security and reducing the need for external memory components. This is complemented by 512 bytes of register RAM, which provides a high-speed workspace for critical data variables.
The peripheral set integrated into the EE87C196MH is extensive and tailored for control applications. Key components include:
A 10-bit Analog-to-Digital Converter (ADC) with a programmable acquisition time and a sample-and-hold circuit, enabling precise measurement of analog signals from sensors.
Two dedicated 16-bit counter/timers and a dedicated 16-bit watchdog timer for robust timing operations and system monitoring.
A High-Speed I/O (HSIO) unit capable of measuring and generating high-resolution pulses, ideal for motor control and capturing external events.
A serial port that can be configured to operate in multiple modes, including asynchronous (UART) and synchronous protocols.
Five 8-bit I/O ports offering extensive digital interfacing capabilities with external logic and devices.
Fabricated on CHMOS technology, the EE87C196MH achieves an effective balance between high-speed performance and low power consumption. Its ability to operate in challenging electrical environments, coupled with its rich feature set, made it a cornerstone of embedded design in its era.
ICGOOODFIND: The Intel EE87C196MH is a quintessential example of a high-integration 16-bit microcontroller, whose advanced architecture—particularly its register-based CPU and innovative Peripheral Transaction Server—delivered the deterministic performance necessary for a generation of advanced real-time embedded systems.
Keywords: 16-bit Microcontroller, Embedded Control, Peripheral Transaction Server (PTS), Real-time System, MCS® 96 Architecture.
