Abstract: Synchronization of display functions and various touch, stylus and/or force sensing functions for devices including a variable refresh rate (VRR) display is disclosed. In some examples, touch, stylus and/or force sensing functions can be synchronized with display frames and a display refresh rate can be adjusted by extended blanking of the display for one or more display frames. In other examples, touch, stylus and/or force sensing functions can be synchronized with display sub-frames and a display refresh rate can be adjusted by extended blanking of the display for one or more display sub-frames. Pre-warning synchronization signals can be generated to prepare one or more scan controllers to implement the appropriate scan events during and after extended blanking periods. Latency between the scan results and the corresponding image on the display can be corrected in software and/or firmware by time-stamping scan results or by dropping scan results from uncompleted scans.

Abstract: Synchronization of display functions and various touch, stylus and/or force sensing functions for devices including a variable refresh rate (VRR) display is disclosed. In some examples, touch, stylus and/or force sensing functions can be synchronized with display frames and a display refresh rate can be adjusted by extended blanking of the display for one or more display frames. In other examples, touch, stylus and/or force sensing functions can be synchronized with display sub-frames and a display refresh rate can be adjusted by extended blanking of the display for one or more display sub-frames. Pre-warning synchronization signals can be generated to prepare one or more scan controllers to implement the appropriate scan events during and after extended blanking periods. Latency between the scan results and the corresponding image on the display can be corrected in software and/or firmware by time-stamping scan results or by dropping scan results from uncompleted scans.

Abstract: A system, device, and method allowing a host device to communicate with, and initialize, an uninitialized peripheral device includes, on the peripheral device, logic for storing a separate mask corresponding to each of a plurality of memory locations, and logic, responsive to a request for reading a memory location, for outputting a bit-wise exclusive-OR of data stored in the memory location and the corresponding mask. The mask is equal to a bit-wise exclusive-OR of a predetermined configuration value and a preset value. Thus, if the memory location is not pre-programmed with configuration information, the bit-wise exclusive-OR of the data stored in the memory location and the corresponding mask results in a valid default configuration value. Once the host device is able to communicate with the peripheral device, the host device programs the peripheral device by storing in the memory location a new data value equal to the bit-wise exclusive-OR of a new configuration value and the corresponding mask.