P2 microSD FAT32 Filesystem

This project provides a robust, high-performance SD card driver for the P2 microcontroller with full FAT32 filesystem support. The driver uses P2 smart pins for hardware-accelerated SPI communication and supports multiple simultaneous file handles.

Features

• FAT32 Filesystem Support: Full read/write access to FAT32-formatted SD cards
• High-Performance SPI: Smart pin hardware acceleration with streamer DMA
• Multi-File Handles: Up to 6 simultaneous file and directory handles (configurable)
• Cross-OS Compatibility: Works with cards formatted on Windows, macOS, and Linux
• SDHC/SDXC Support: Block-addressed cards tested up to 128GB (reformatted as FAT32)
• CRC Validation: Hardware-accelerated CRC-16 on all data transfers
• Directory Operations: Create, navigate, and enumerate directories (index-based and handle-based)
• File Operations: Create, open, read, write, seek, rename, delete
• Live Timestamps: setDate()/getDate() with 2-second auto-advance for file creation and modification stamps
• Auto-Flush: Dirty handles flushed after 200ms idle — protects against card removal data loss
• Non-Blocking Async I/O: Optional startReadHandle()/startWriteHandle() for overlapping computation with SD I/O (SD_INCLUDE_ASYNC)
• Defragmentation: compactFile() relocates fragmented files into contiguous clusters; createFileContiguous() pre-allocates contiguous space (SD_INCLUDE_DEFRAG)
• Built-in Card Formatter: Format any SD card as FAT32 directly from the P2 — no PC required
• Filesystem Repair: Integrated read-only audit (39 checks) and 4-pass fsck with auto-repair
• Multi-Cog Safe: Dedicated worker cog with hardware lock serialization
• Per-Cog Working Directory: Each cog maintains its own CWD for safe concurrent navigation
• Regression Tested: 465 automated tests across 25 test suites

Hardware Requirements

• Parallax Propeller 2 (P2) microcontroller
• P2 Edge Module (P2-EC or P2-EC32MB)
• microSD Add-on Board (#64009) - provides the microSD card slot
• microSD card (SDHC or SDXC — format with the included format utility or any OS formatter)

Notes

• This is a regression test certified driver for the P2 Edge boards.
• This object v1.5.3 will be updated periodically. For the latest release, visit the Releases Page
• This started as Chris Gadd's #4269 SD Driver updated for OS Interchange and write failure protection, and is now certified for high-performance