Intel AN87C196CA: An In-Depth Technical Overview of the 16-Bit Embedded Controller
The Intel AN87C196CA stands as a significant milestone in the evolution of 16-bit embedded controllers, representing a highly integrated solution designed for complex, real-time control applications. As a member of the MCS® 96 family, this microcontroller combines high computational throughput with a rich set of peripheral features, making it a cornerstone in industrial automation, automotive systems, and advanced consumer electronics during its era.
Architectural Foundation and Core Performance
At its heart, the AN87C196CA is built upon a 16-bit CHMOS CPU core with a register-to-register architecture. This design eliminates the accumulator bottleneck common in earlier microcontrollers, significantly enhancing data throughput and operational efficiency. The core operates at a maximum clock frequency of 16 MHz, enabling it to execute most instructions in a single state time (500 ns), resulting in a peak performance of 2 million instructions per second (MIPS). A key feature of its computational prowess is the hardware multiplier/divider, which allows for the execution of a 16x16-bit multiplication or a 32/16-bit division in just 1.75 µs, a critical capability for mathematical-intensive control algorithms.
Advanced Memory Subsystem
The microcontroller features a comprehensive memory architecture. It incorporates 8 KB of on-chip EPROM for non-volatile program storage, allowing for firmware updates and field programmability. This is complemented by 256 bytes of register RAM, which serves as the primary working register file. This RAM is accessed in a single clock cycle, providing the performance of a large register set. Furthermore, it supports a programmable memory controller for expanding address space up to 64 KB, with chip select signals to interface seamlessly with external ROM, RAM, and peripheral devices.
Rich Integrated Peripheral Set
The integration of sophisticated peripherals is what truly defines the AN87C196CA. Its peripheral set is tailored for precision control and communication:
High-Speed I/O Unit: This dedicated subsystem includes 16-bit timers/counters and a 4-channel PWM (Pulse Width Modulator) output, ideal for motor control and power conversion.
10-Bit Analog-to-Digital Converter (ADC): The chip features a 10-bit ADC with a sample-and-hold circuit and up to 13 analog input channels. With a conversion time of just 22 µs, it provides the necessary speed for real-time sensor data acquisition.
Serial Communications: It is equipped with both a full-duplex UART (Serial Port) for asynchronous communications and a synchronous Serial I/O Port for high-speed data transfer with peripheral chips.
Event Processor Array (EPA): A standout feature, the EPA integrates capture/compare modules and a dedicated timer to handle input and output events with minimal CPU overhead, ensuring precise timing and rapid response to external interrupts.
Watchdog Timer: An essential feature for robust system design, the watchdog timer automatically resets the processor in the event of software malfunctions, enhancing system reliability.
System Integration and Power Management
Fabricated on Intel's CHMOS technology, the AN87C196CA offers a compelling blend of high speed and low power consumption. It supports multiple power-saving modes, including idle and power-down modes, which drastically reduce power consumption during periods of inactivity. Its 68-pin PLCC package provides a compact form factor while offering the necessary I/O pins to interface with the external world.
ICGOOODFIND
The Intel AN87C196CA is a quintessential example of a high-performance, fully-integrated 16-bit embedded controller. Its powerful register-based CPU, combined with its extensive and specialized peripheral set—including the high-speed EPA, PWM, and ADC—made it an indispensable component for designing sophisticated real-time control systems. It successfully balanced raw processing power with functional integration, setting a standard for subsequent microcontrollers in demanding industrial and automotive applications.
Keywords: 16-Bit Microcontroller, Embedded Control, Real-Time Systems, Peripheral Integration, MCS® 96 Architecture
