eosflash

Cross-platform CLI for inspecting, transforming, and writing E-MU E4 / EIV / E-Synth sampler firmware (EOS). Classic and Ultra generations. Runs natively on Linux and modern Windows. Supports raw disks, legacy E-MU DOS executables, and full and partial ROMs.

Note: Use emu.tools to update E4 samplers via MIDI — no floppies required!

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Usage

Inspect a file or floppy disk

eosflash verify eos.img                # Verify/Show RAW disk image
sudo eosflash verify /dev/fd0          # (Linux)   physical floppy — requires sudo
eosflash verify a:                     # (Windows) physical floppy

Compare two sources

eosflash verify a.eos b.eos            # compare payloads of two OS binaries
sudo eosflash verify eos.img /dev/fd0  # (Linux)   RAW image vs physical floppy
eosflash verify eos.exe a:             # (Windows) DOS executable vs physical floppy

Export between formats

eosflash export os.exe --img out.img --eos out.eos  # DOS executable -> RAW image, OS binary
eosflash export os.dli --eos out.eos                # EOSLoader .dli -> compressed OS binary
eosflash export os.eos --dli out.dli                # OS binary -> EOSLoader .dli (Ultra only)

.dli (EOSLoader "DownLoad Image") files are accepted as a source anywhere a .eos/.img/.rom is, and --dli emits one. This is the only distribution form of the 4.59beta7 and 4.60a Ultra OS builds.

Write floppy disk(s)

Works with both OS and Flash Prep sources.

sudo eosflash write os.eos --drv /dev/fd0     # (Linux)   create OS disk
eosflash write os.img flashprep.img --drv a:  # (Windows) OS and Flash Prep

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Advanced ROM manipulation

The flash command splits, combines, compresses and decompresses ROM binaries.

# Combine / split IC dumps
eosflash flash low.bin high.bin --rom full.rom       # combine two IC halves -> ROM
eosflash flash full.rom --lo low.bin --hi high.bin   # split ROM -> two hi/lo halves

# Extract / reassemble payloads
eosflash flash full.rom --eos os.eos --btl boot.btl  # extract OS + bootloader from ROM
eosflash flash os.eos boot.btl --rom full.rom        # reassemble OS + bootloader -> ROM

# Compress / decompress
eosflash flash compressed.eos --eos out.eos --4mb    # decompress 2MB -> 4MB compatible
eosflash flash uncompressed.eos --eos out.eos --2mb  # compress to fit in 2MB target

What to avoid

• Don't flash Ultra OS onto a Classic - Classic (1st/2nd gen EIV/E4) uses Motorola 68020; E4 Ultra uses Coldfire MCF5206E. They are not compatible.
• Don't write a corrupted source - It won't boot on real hardware. Use --force only to investigate corrupted files.
• Don't use a 64KB bootloader with a 4MB ROM target - The 4MB FlashROM has a different RAM map and IC layout; a 64 KB bootloader will not boot.

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Bugs / support

Floppy drive issues (bad sectors, mechanical failures) are normal, use freshly formatted disks before writing OS.

For everything else: open an issue here on GitHub or ping @nkrypth on the Madlabz Discord: madlabz.info