Claude-skill-registry fdc-expert
Expert on NEC µPD765 Floppy Disk Controller for ES-1841. Provides guidance on floppy disk access, sector read/write, seek operations, command phases, and DMA integration.
install
source · Clone the upstream repo
git clone https://github.com/majiayu000/claude-skill-registry
Claude Code · Install into ~/.claude/skills/
T=$(mktemp -d) && git clone --depth=1 https://github.com/majiayu000/claude-skill-registry "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/data/fdc-expert" ~/.claude/skills/majiayu000-claude-skill-registry-fdc-expert && rm -rf "$T"
manifest:
skills/data/fdc-expert/SKILL.mdsource content
FDC Expert - NEC µPD765 / Intel 8272A
Expert knowledge for the ES-1841's floppy controller.
Key Specifications
| Property | Value |
|---|---|
| I/O Ports | |
| DMA Channel | 2 |
| IRQ | 6 |
| Drives | Up to 4 |
I/O Ports
| Port | Read | Write |
|---|---|---|
| - | Digital Output (DOR) |
| Main Status (MSR) | - |
| Data (FIFO) | Data (FIFO) |
DOR - Digital Output (3F2h
)
3F2h| Bits | Function |
|---|---|
| 0-1 | Drive select |
| 2 | Reset (0=reset) |
| 3 | DMA/IRQ enable |
| 4-7 | Motor on (drives 0-3) |
MSR - Main Status (3F4h
)
3F4h| Bit | Function |
|---|---|
| 7 | RQM - Ready for data |
| 6 | DIO - Direction (1=read) |
| 4 | CB - Command busy |
Command Phases
- Command: Write to
(RQM=1, DIO=0)3F5h - Execution: DMA transfer
- Result: Read from
(RQM=1, DIO=1)3F5h
Key Commands
| Command | Code |
|---|---|
| Read Data | |
| Write Data | |
| Recalibrate | |
| Seek | |
| Sense Interrupt | |
Drive Types
| Type | Tracks | Sectors | Capacity |
|---|---|---|---|
| 5.25" DD | 40 | 9 | 360 KB |
| 3.5" DD | 80 | 9 | 720 KB |
| 3.5" HD | 80 | 18 | 1.44 MB |
References
See references/ for detailed documentation.