OSSC potential incompatibilities

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Incompatibility due to display tolerance

Below are listed consoles which may be incompatible with certain displays when used with OSSC. Home computers and more exotic arcade boards are not included since their outputs often deviate from PAL/NTSC spec to a degree that they are not generally compatible with TVs but with PC monitors only. Capture card compatibility is neither considered since with some exceptions they are the most picky devices when it comes to non-standard refresh rates and line counts.

As a rule of thumb, consoles with linedoubled output with >1 scanlines off 525/625 line spec or >0.5Hz off 50/60Hz refresh can be considered potentially incompatible for displays.

Console Reason Fix if any Test method
NESRGB / SNES in 60Hz mode Hsync period is not constant, causing some jitter to output clock. Some displays are sensitive to this and cannot properly lock to the signal (low receiver PLL bandwidth). De-jitter modification No known external test method.
Neo Geo 264-line output becomes 528 when linedoubled. MVS additionally outputs 59.18Hz refresh rate. Crystal swap for refresh rate normalization
ModeLine "MVS_240p_x2" 26.810 720 736 798 858  480 489 495 528  -hsync -vsync
PSX in 50Hz non-interlaced (288p) mode 314-line output becomes 628 when linedoubled. Dual-frequency oscillator (DFO) for refresh rate normalization
ModeLine "PSX_288p_x2" 27.000 720 732 796 864  576 581 587 628  -hsync -vsync
PAL Saturn in 60Hz mode 59.37 Hz vertical refresh rate Dual-frequency oscillator (DFO)
ModeLine "PAL_Saturn_240p_x2" 26.794 720 736 798 858  480 489 495 526  -hsync -vsync

Incompatibility due to sync characteristics

Below are listed consoles which are incompatible with OSSC's default settings regardless of display. Some are simply fixed by a menu setting, others may need extra hardware.

Console Reason/symptom Fix if any
Neo Geo MV-1A and MV-1FZ Significant hsync period variation during vblank H-PLL pre and post coast -> 3, Hsync tolerance -> 10us (or higher)
Jaguar in 50Hz non-interlaced (288p) mode Output uses constant even field indicator since boot, OSSC can't lock properly AV3 input (different sync processing chain) e.g. with Sync Strike
PSX SCPH-100 (unverified) No sync detected?
Intellivision with RGB Mod No hsync pulses around vsync - incompatible with digitiser No solution as yet.
RGB modded French N64 (unverified) Unstable sync regardless of settings?

Other incompatibilities

Consoles/hardware with other issues are listed here.

Console Reason/symptom Fix if any
Sega Megadrive Mk1 Bad audio quality using Stereo RGB cable with headphone socket audio Fixed in latest firmware. Affects OSSC 1.6 only

Software incompatibilities

Any software that has unusal incompatibilities will be listed here. Note this does not include software that switches 240p/480i in game, which may or may not render the game unplayable.

Game Platform Reason/symptom Fix if any
Bugs Bunny in Double Trouble Sega Megadrive/Genesis Uses some unknown tricks on graphics/timing which confuses OSSC Currently no known fix.