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Utilities/LegacyBoot/README.md

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BootInstall

This tool installs legacy DuetPkg environment on GPT-formatted disk to enable UEFI environment on BIOS-based systems.

Linux & macOS

The tool supports Linux and macOS natively.

Windows

For Windows one will have to perform steps manually with PowerShell. Rough description is provided below.

  1. Dump MBR (replace PHYSICALDRIVE0 with your drive). You might want to copy old_mbr.bin somewhere for backup purposes.
powershell
$disk = [System.IO.File]::Open("\\.\PHYSICALDRIVE0", [System.IO.FileMode]::Open)
$buffer = New-Object byte[] 512
$disk.Read($buffer, 0, 512) | Out-Null
[System.IO.File]::WriteAllBytes("old_mbr.bin", $buffer)
$disk.Close()
  1. Add boot0 to MBR (uses dd command from WSL).
sh
cp old_mbr.bin mbr.bin
dd if=boot0 of=mbr.bin bs=1 count=446 conv=notrunc
  1. Assign a letter to the EFI partition to perform raw access. Use your own disk number (here 0) and partition number (here 1) in diskpart commands. Select another letter if X is unavailable.
powershell
dispart
> select disk 0
> select part 1
> assign letter X
> quit
fsutil volume dismount X:
  1. Dump PBR (replace X: with your volume). You might want to copy old_pbr.bin somewhere for backup purposes.
powershell
$disk = [System.IO.File]::Open("\\.\X:", [System.IO.FileMode]::Open)
$buffer = New-Object byte[] 512
$disk.Read($buffer, 0, 512) | Out-Null
[System.IO.File]::WriteAllBytes("old_pbr.bin", $buffer)
$disk.Close()
  1. Update PBR with boot1f32 (uses dd command from WSL).
sh
cp boot1f32 pbr.bin
dd if=old_pbr.bin of=pbr.bin skip=3 seek=3 bs=1 count=87 conv=notrunc
dd if=/dev/random of=pbr.bin skip=496 seek=496 bs=1 count=14 conv=notrunc
  1. Write MBR (replace PHYSICALDRIVE0 with your drive).
powershell
$disk = [System.IO.File]::Open("\\.\PHYSICALDRIVE0:", [System.IO.FileMode]::Open)
$buffer = [System.IO.File]::ReadAllBytes("mbr.bin")
$disk.Write($buffer, 0, $buffer.Length)
$disk.Close()
  1. Write PBR (replace X: with your volume).
powershell
$disk = [System.IO.File]::Open("\\.\X:", [System.IO.FileMode]::Open)
$buffer = [System.IO.File]::ReadAllBytes("pbr.bin")
$disk.Write($buffer, 0, $buffer.Length)
$disk.Close()