TGA_VALID_BLANK
TGA_WRITE_REG(par, TGA_VALID_VIDEO | TGA_VALID_BLANK, TGA_VALID_REG);
vvvr &= ~(TGA_VALID_VIDEO | TGA_VALID_BLANK);
TGA_WRITE_REG(par, vvvr | TGA_VALID_VIDEO | TGA_VALID_BLANK,
TGA_WRITE_REG(par, vvvr | TGA_VALID_BLANK, TGA_VALID_REG);
TGA_WRITE_REG(par, vvvr | TGA_VALID_BLANK, TGA_VALID_REG);
TGA_WRITE_REG(par, vvvr | TGA_VALID_BLANK, TGA_VALID_REG);