The Intel P8271 is a single-chip Programmable Floppy Disk Controller (FDC) designed to interface up to four floppy disk drives with 8-bit microprocessor systems, such as Intel's MCS-80/85 series. Introduced in the late 1970s, it was notably used in systems like the BBC Microcomputer. The P8271 supports IBM 3740 soft-sectored format and is compatible with single-density FM encoding.
Key Features:
Drive Support: Interfaces with one to four floppy disk drives.
Encoding: Supports single-density Frequency Modulation (FM) encoding; does not support double-density Modified Frequency Modulation (MFM).
Data Handling: Internal generation and checking of Cyclic Redundancy Check (CRC) for data integrity.
Programmability: Allows programmable record lengths, step rates, settle times, head load/unload times, and index count.
Multi-Sector Capability: Supports multi-sector transfers to enhance data throughput.
Automatic Head Positioning: Features automatic read/write head positioning and verification.
Command Set: Includes high-level commands for reading, writing, scanning, and formatting operations.
Interface: Compatible with Intel's 8080 microprocessor systems and supports DMA operations via the Intel 8257 DMA controller.
Package: 40-pin Dual In-line Package (DIP).
Applications:
Vintage computing systems requiring floppy disk interfacing.
Restoration projects for systems like the BBC Microcomputer.
Educational purposes for understanding early computer hardware design.
