The MD8155H/BC, manufactured by Intel, is a Programmable Peripheral Interface (PPI) with RAM and Timer. The 'H' likely indicates a higher-speed version or variation, and '/BC' signifies a specific revision or screening level. Similar to the MD8155/B, it's designed to interface with Intel microprocessors, providing parallel I/O ports, RAM, and timer capabilities for diverse control and data storage applications.

Applications

• Microprocessor-Based Control Systems: Used for I/O expansion and control in systems based on the Intel 8085 or similar microprocessors.
• Industrial Automation Equipment: Employed in legacy industrial controllers for interfacing with sensors, actuators, and displays.
• Data Logging and Acquisition Systems: Utilized for temporary data storage and interfacing with data acquisition hardware.
• Embedded Systems: Suitable for embedded applications where programmable I/O, RAM, and timing functions are needed.

Features

• Three Programmable I/O Ports: Configurable for input, output, or bidirectional data transfer.
• 256 Bytes of Static RAM: Provides on-chip memory for data buffering and storage.
• Programmable Timer: Used for generating time intervals, controlling external events, and implementing real-time functions.
• Interrupt Generation: Can generate interrupts based on timer events or I/O port activity.
• Multiplexed Address and Data Bus: Simplifies interfacing with microprocessors by sharing address and data lines.

Benefits

• Flexible I/O Interface: The programmable I/O ports adapt to different interfacing requirements.
• Integrated RAM and Timer: Reduces the need for external components, saving board space and cost.
• Simplified System Design: Integration of multiple functions simplifies circuit design and lowers complexity.
• Real-Time Control Capabilities: The programmable timer enables precise timing and control of external devices.

The Intel MD8155H/BC offers a comprehensive solution for interfacing microprocessors with external devices and managing data. Its combination of programmable I/O, RAM, and timer functions makes it suitable for a wide range of applications in industrial control, data acquisition, and embedded systems. The 'H' designation likely indicates improved performance or features compared to the standard MD8155, possibly including a higher clock speed or enhanced interrupt handling capabilities. This integrated approach simplifies system design, reduces component count, and lowers overall system cost. While more advanced peripherals are available, the MD8155H/BC remains a viable option for maintaining legacy systems and for applications where its capabilities are sufficient.