CR50
unsigned char CR50, CR51, CR53, CR55, CR58, CR5B, CR5D, CR5E;
reg->CR50 = 0;
reg->CR50 = 0x10;
reg->CR50 = 0x30;
reg->CR50 |= 0x40;
reg->CR50 |= 0x80;
reg->CR50 |= 0x00;
reg->CR50 |= 0x01;
reg->CR50 |= 0xc0;
reg->CR50 |= 0x81;
reg->CR50 |= 0xc1; /* Use GBD */
vga_out8(0x3d5, reg->CR50, par);
reg->CR50 = vga_in8(0x3d5, par);
vga_out8(0x3d5, reg->CR50, par);