[Main]
Name=OSContrastDn
Type=Function
Subtype=ROM Call
Header Files=system.h
Definition=void OSContrastDn (void);
Real Definition=#define OSContrastDn() ({_rom_call(void,(void),297) (); asm ("":::"d3","d4");})
See Also=OSContrastUp, OSContrastAddress, OSContrastValue

[ROM Call]
Index=$297

[Description]
Decreases the contrast.

[Explanation]
OSContrastDn decreases the display contrast.
It is actually a library function calling the real TIOS function called OSContrastDn,
because the TIOS function destroys the content of a register which needs to be preserved.

[References]
Out=AB_getGateArrayVersion
