PSP Homebrew Testing (PPSSPP on Windows)

Test workflow for PSP homebrew builds using PPSSPP on Windows. Covers deploying EBOOTs, capturing visual output, reading debug logs, and managing PPSSPP process lifecycle.

Prerequisites

• PPSSPP installed on Windows (/path/to/PPSSPP.exe)
• PSP homebrew EBOOT.PBP built with pspdev toolchain
• Game data files (CRITTER.DAT, MASTER.DAT, DATA/ etc.) alongside EBOOT

PPSSPP Config Management

Config lives at: <memstick>/PSP/SYSTEM/ppsspp.ini

Key settings to toggle:

NOTE: Changes to ppsspp.ini only take effect on PPSSPP restart. Running PPSSPP processes cache the config at startup.

Deploying to PPSSPP

1. Place EBOOT.PBP + assets in <memstick>/PSP/GAME/<SOMEID>/
   • Folder name (e.g. FOUT00002) becomes the game's entry name in PPSSPP browser
   • Folder ID (6 chars from PARAM.SFO) used for playtime tracking in [PlayTime] section
2. Launch PPSSPP with game path as argument:

   /f/emulators/ppsspp/PPSSPPWindows64.exe "/f/emulators/ppsspp/memstick/PSP/GAME/FOUT00002/EBOOT.PBP"

3. Alternative: launch PPSSPP normally, navigate game browser to the entry, press Enter/X

Capturing Screenshots

The FPS counter and other PPSSPP overlays are NOT captured by PSP internal framebuffer dumps (sceIoWrite, etc.). They render in PPSSPP's Vulkan/D3D presentation layer.

Use Windows screen capture (PowerShell) to capture the full PPSSPP window including overlays:

Add-Type -AssemblyName System.Drawing,System.Windows.Forms
$bounds = [System.Windows.Forms.Screen]::PrimaryScreen.Bounds
$bmp = New-Object System.Drawing.Bitmap $bounds.Width, $bounds.Height
$g = [System.Drawing.Graphics]::FromImage($bmp)
$g.CopyFromScreen($bounds.X, $bounds.Y, 0, 0, $bounds.Size)
$bmp.Save("/tmp/screenshot.png", [System.Drawing.Imaging.ImageFormat]::Png)
$g.Dispose(); $bmp.Dispose()

Run from git-bash via:

powershell.exe -ExecutionPolicy Bypass -File C:/path/to/script.ps1

IMPORTANT: The PPSSPP window must be visible and not minimized. Use ShowWindow + SetForegroundWindow Win32 APIs to activate it before capture if needed.

Reading PSP Debug Logs

PSP homebrew can write debug output via sceIoWrite to the memstick. Common paths:

• <memstick>/psp_debug.txt
• <memstick>/palette_log.txt
• <memstick>/showrect_log.txt
• <memstick>/ppsspp.log (PPSSPP emulator log)

To check if the game is actually running (vs PPSSPP sitting on game browser):

• Check PSP debug logs for svga_init success, createRenderer OK, frame loop timestamps
• Check PPSSPP log for game load traces
• Compare log file modification timestamps

Process Management

Kill all zombie PPSSPP processes:

cmd.exe //c "taskkill /F /IM PPSSPPWindows64.exe"

Launch game directly (background):

/f/emulators/ppsspp/PPSSPPWindows64.exe "/f/emulators/ppsspp/memstick/PSP/GAME/FOUT00002/EBOOT.PBP"

Send keystrokes to activate and control PPSSPP:

Add-Type -AssemblyName System.Windows.Forms
Add-Type @"
using System; using System.Runtime.InteropServices;
public class WinAPI {
    [DllImport("user32.dll")] public static extern bool SetForegroundWindow(IntPtr hWnd);
    [DllImport("user32.dll")] public static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);
}
"@
$hwnd = (Get-Process PPSSPPWindows64)[0].MainWindowHandle
[WinAPI]::ShowWindow($hwnd, 1); [WinAPI]::SetForegroundWindow($hwnd)
Start-Sleep -Milliseconds 300
[System.Windows.Forms.SendKeys]::SendWait("~")  # Enter

Pitfalls

• Zombie processes: PPSSPP processes accumulate if not cleanly exited. Always taskkill /F before restarting.
• Config changes ignored: PPSSPP reads ppsspp.ini at startup. Changes to a running instance's config file have no effect.
• Vulkan overlay not in framebuffer dumps: The FPS counter and emulator overlays are rendered by PPSSPP's GPU presentation layer. Internal PSP framebuffer dumps (via sceIoWrite) will NOT show them. Always use Windows CopyFromScreen for overlay-inclusive screenshots.
• AutoRun ambiguity: AutoRun=True runs the LAST booted game. A fresh PPSSPP install with no boot history goes to game browser regardless.
• SendKeys unreliability: SendKeys only works if the target window is in the foreground. SetForegroundWindow may fail if another app (like a UAC prompt or terminal) has focus.

See Also

• windows-environment skill — general Windows/git-bash usage
• references/ppsspp-settings.md — PPSSPP config details