Program compatibility

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Revision as of 05:53, 29 July 2015 by Rainwarrior (talk | contribs) (RTC demo also suffers from DPCM conflict)
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This page describes defects in homebrew games. For defects in games prior to 1996, see Game bugs.

Homebrew development is as subject to bugs as old software was, but many suffer from additional compatibility problems with the NES hardware due to being tested on emulators exclusively. This page is an incomplete list of homebrew releases that have known bugs, or especially hardware compatibility problems.

For a partial list of homebrew projects, see: Projects

Title Year Problem Description
Dikki Painguin in: TKO for the Third Reich (ROM) 2004 Incorrectly implemented parallax scrolling effect causes a severe graphical problem.
Final Fantasy II (English translation, Neo Demiforce) (Patch) 1998 Version 1.02 and 1.03 — graphic glitches during intro, no text during prologue (blue screen without text).

Caused by incorrect setting of nametables in PPUCTRL, misuse of PPUSCROLL, and reading of PPUSTATUS to detect VBlank.[1]

LAN Master (ROM) 2012 APU DMC causes byte deletions when reading back nametables from $2007 if a dialog is being displayed during a drum hit.
Mouser (ROM) 1998 Severe graphical problems prevent any useful gameplay.

Its author later created a sequel that addressed the compatibility problems.[2]

RTC Demo (ROM) 2000 Graphical glitches at the raster-bars portion because it incorrectly expects a sprite-0 hit on X=255.[3]

The sound-mode portion erratically advances tracks due to DPCM conflict with the controller read.

Ironically, this demo has a screen that attempts to detect the user of an emulator and warns the user that they are not playing it on hardware (this screen still triggers if played on a PowerPak).

Sack of Flour, Heart of Gold (ROM) 2002 Severe graphical problems on some screens due to $2007 access outside of vblank.[4]

References