SD Card Setup¶

PicoIDE uses a microSD card to store disk and CD-ROM images along with configuration settings.

Requirements¶

microSD card (newer cards are recommended)
FAT32 or exFAT formatted with MBR partitioning. Formatting with the SD Association's SD Card Formatter is strongly recommended!

Card Selection

While most microSD cards work fine, higher-speed cards (Class 10 or UHS-I) provide better performance.

Directory Layout¶

The following is an example directory structure on the SD card. cdrom/ and hdd/ are default locations for those types of images but they can be put elsewhere on the card.

/
├── cdrom/                      # CD-ROM images (ATAPI mode)
│   ├── game.iso
│   ├── album.cue
│   ├── album.bin
│   └── Big Game/               # Subdirectories supported
│       └── Disc 1.iso
│       └── Disc 2.iso
├── hdd/                        # Hard disk images (IDE mode)
│   ├── dos622.img
│   └── windows98.vhd
├── firmware/                   # Firmware update files
│   ├── picoide.uf2             # Main board firmware
│   └── picoide-frontpanel.bin  # Front panel firmware
└── picoide.ini                 # Configuration file

Supported File Formats¶

ATAPI Mode (CD-ROM)¶

Extension	Description
`.iso`	ISO 9660 disc image
`.cue`	CUE sheet with associated `.bin` file(s)
`.toast`	Disc image commonly used on vintage Macs

bin/cue Images

For bin/cue CD images, place the .cue file and all referenced .bin files in the same directory. PicoIDE supports audio tracks for CD music playback.

IDE Mode (Hard Disk)¶

Extension	Description
`.vhd`	Virtual Hard Disk (supports baked-in CHS geometry)
`.img`	Raw disk image
`.hda`	Raw disk image
`.hdf`	Raw disk image (Amiga, RDB format only)

VHD Images

Only fixed VHD images are supported. Dynamic and differencing VHD images will not work.

86Box is great for creating VHD images with arbitrary CHS geometry and setting them up ahead of time.

HDF Images

Amiga "hardfile" HDF images are not supported - only raw images including the RDB are supported. Images created from actual Amiga disks or partitioned RDB images from Amiga emulators will work.

Configuration File¶

The picoide.ini file controls device behavior and auto-loading. Place it in the root of your SD card. If you have the front panel installed, you can also edit this file from the web interface.

Example Configuration¶

# PicoIDE Configuration File

[device]
# Device type: IDE (hard disk) or ATAPI (CD-ROM)
type = ATAPI

[ide]
# Full path to hard disk image (leave empty for first found)
image_path = /hdd/windows98.img

# Directory to browse for hard disk images
browse_dir = /hdd

[atapi]
# Full path to CD-ROM image (leave empty for first found)
image_path = /cdrom/game.iso

# Directory to browse for CD-ROM images
browse_dir = /cdrom

# Auto-load image at boot time
auto_load = true

Configuration Reference¶

`[device]` Section¶

Setting	Values	Default	Description
`type`	`IDE`, `ATAPI`	`ATAPI`	Device emulation mode

`[ide]` Section¶

Setting	Description
`image_path`	Full path to auto-load (empty = first alphabetically in browse_dir)
`browse_dir`	Directory for image browsing (default: `/hdd`)

`[atapi]` Section¶

Setting	Description
`image_path`	Full path to auto-load (empty = first alphabetically in browse_dir)
`browse_dir`	Directory for image browsing (default: `/cdrom`)
`auto_load`	`true`, `false`

Auto image_path Updating

When you select a different image using the front panel or host control, the configuration file is automatically updated to remember your selection.

`[overrides]` Section¶

Advanced settings to override the maximum transfer mode, IDENTIFY responses, etc. These are primarily useful for troubleshooting compatibility issues with certain vintage computers.

Setting	Values	Default	Description
`max_pio_mode`	`0`-`4`	`4`	Maximum PIO transfer mode
`max_mwdma_mode`	`0`-`2` or `-1`	`2`	Maximum Multi-word DMA mode (`-1` disables DMA)
`disable_iordy`	`true`, `false`	`false`	Disable IORDY flow control
`sector_delay_us`	`0`-`1000`	`0`	Delay in microseconds between sectors during multi-sector PIO reads
`bus_delay`	`1.0`-`6.0`	`1.0`	Bus timing delay factor for slow or noisy IDE buses

Example for forcing PIO-only operation:

[overrides]
max_mwdma_mode = -1

Example for disabling IORDY flow control (for older systems with IORDY issues, or for a small speed boost on tolerant systems):

[overrides]
disable_iordy = true

Example for fixing hangs during boot on systems with BIOSes that expect to see BSY between sectors:

[overrides]
sector_delay_us = 100

Example for slowing bus timing on very old systems (e.g., IBM 5170):

[overrides]
bus_delay = 6.0

Auto-Mount Behavior¶

When auto_load is enabled in ATAPI mode:

With image_path set: Loads the specified image
With image_path empty: Loads the first image found alphabetically in the browse directory

This allows for completely headless operation - just power on and the configured image is ready.

Auto-mount in IDE mode

If the device is in IDE mode and an image cannot be loaded, it will result in an error as PicoIDE only supports emulating a fixed (non-removable) disk.

Tips¶

Organizing Images¶

Use subdirectories to organize your collection:

/cdrom/
├── games/
│   ├── doom.iso
│   ├── quake.iso
│   └── big game/
│       ├── disc 1.iso
│       └── disc 2.iso
├── os install/
│   └── win98cd.iso
└── music/
    └── album.cue

Case Insensitivity¶

Paths and file names specified in picoide.ini are case-insensitive due to the FAT file system on the SD card.