VGA_CRTC_LINE_COMPARE
vga_wcrt(regbase, VGA_CRTC_LINE_COMPARE, 0xff);
par->crtc[VGA_CRTC_LINE_COMPARE] = 0xFF;
reg.crt[VGA_CRTC_LINE_COMPARE] = 0xff;
write3X4(par, VGA_CRTC_LINE_COMPARE, 0xFF);
par->crtc[VGA_CRTC_LINE_COMPARE] = 0xFF;