VGA_CRTC_PRESET_ROW
vga_wcrt(cinfo->regbase, VGA_CRTC_PRESET_ROW, 0x00);
vga_wcrt(regbase, VGA_CRTC_PRESET_ROW, 0);
par->crtc[VGA_CRTC_PRESET_ROW] = 0;
write3X4(par, VGA_CRTC_PRESET_ROW, 0);
par->crtc[VGA_CRTC_PRESET_ROW] = 0;