The MC6802P is an 8-bit microprocessor from Motorola (later Freescale Semiconductor, now NXP). It is a classic processor that saw widespread use in the late 1970s and early 1980s. It’s closely related to the MC6800 but integrates a clock oscillator and RAM on the same chip, making it a more complete single-chip solution.

Applications

• Early microcomputers and personal computers
• Industrial control systems
• Automotive control systems
• Educational trainers and development boards
• Arcade games
• Early point-of-sale systems.

Features

• 8-bit data bus
• 16-bit address bus (64KB addressable memory)
• On-chip clock oscillator
• 128 bytes of on-chip RAM
• TTL compatible inputs and outputs
• Single 5V power supply
• Interrupt handling capability
• Non-maskable interrupt (NMI)
• Three-state control for memory and I/O expansion.

Benefits

• Simplified system design with integrated clock and RAM
• Lower system cost compared to using separate components
• Easy to interface with standard TTL logic
• Widely available documentation and software support
• Reliable operation in various environments
• Well-suited for real-time control applications.

Additional Details

The MC6802P typically comes in a 40-pin DIP (Dual In-line Package). It requires external ROM (Read-Only Memory) or EPROM (Erasable Programmable ROM) to store the program code. The processor can be clocked using either an external crystal or an RC network. The reset input initializes the processor and starts execution from a predefined address. The 128 bytes of on-chip RAM can be used for data storage and stack operations. Interfacing to peripherals is typically done through parallel ports. The instruction set includes arithmetic, logical, and data transfer instructions. Debugging is typically done using an oscilloscope and logic analyzer, as well as available assembler/disassembler tools. The processor operates in a single-phase clock mode. Proper power supply decoupling is required to minimize noise.