path: root/qemu-options.hx
diff options
Diffstat (limited to 'qemu-options.hx')
1 files changed, 19 insertions, 0 deletions
diff --git a/qemu-options.hx b/qemu-options.hx
index 3e8085d463..0682338e9f 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -975,6 +975,25 @@ Valid optional properties are
@item retrace=dumb|precise
Select dumb (default) or precise VGA retrace logic, useful for some
DOS games/demos.
+@item cga_hacks=@var{hack1}[+@var{hack2},[...]]
+Enable various extra CGA compatibility hacks for programs that are
+trying to directly set CGA modes without BIOS assistance nor
+real knowledge of EGA/VGA. These might only work with -vga std.
+Valid hacks are
+@table @option
+@item palette_blanking
+Wait to blank the screen until palette registers seem to actually be
+modified, instead of blanking it as soon as the palette address bit (0x10)
+of the attribute address register (0x3c0) is cleared.
+@item font_height
+Ignore attempts to change the VGA font height (index 9),
+cursor start (index 10), and cursor end (index 11) of the CRTC control
+registers (0x3d5) if trying to set them to the default for CGA fonts
+instead of VGA fonts.
+@item all
+Enable all CGA hacks. More CGA hacks may be added in future versions
+of qemu.
+@end table
@end table