Various implementations disclosed herein include devices, systems, and methods that buffer events in device memory during synchronous readout of a plurality of frames by a sensor. Various implementations disclosed herein include devices, systems, and methods that disable a sensor communication link until the buffered events are sufficient for transmission by the sensor. In some implementations, the sensor using a synchronous readout may select a readout mode for one or more frames based on how many of the pixels are detecting events. In some implementations, a first mode that reads out only data for a low percentage of pixels that have events uses the device memory and a second mode bypasses the device memory based on accumulation criteria such as high percentage of pixels detecting events. In the second mode, less data per pixel may be readout.