For touch screen displays, information needs to be fed from the screen back to the system. The DS90UB903/04 are ideal for touch screen applications because of continuous backchannel bidirectional control and 18-bit color support. This is very typical for display applications and this chipset has dedicated inputs for the synchronization signals, each of which is Horizontal Sync, Vertical Sync and Data Enabled. There are dedicated GPIOs and a channel back from the deserializer to the serializer on this chipset. In touch screen applications, this may be used to interrupt and let the host device know that there is touch screen information that the host can read over I²C. Finally, error checking with CRC over the backchannel is available.