SLUSDU0 September 2019 BQ21061
The MR input has three main functions in the BQ21061. First, it serves as a means to wake the device from Ship Mode. Second, it serves as a short button press detector, sending an interrupt to the host when the button driving the MR pin has been pressed for a given period of time. This allows the implementation of different functions in the end application such as menu selection and control. And finally it serves as a mean to get the BQ21061 to reset the system by performing a power cycle (shut down PMID and automatically powering it back on) or go to Ship Mode after detecting a long button press. The timing for the short and long button press duration is programmable through I2C for added flexibility. Note that if a specific timer duration is changed through I2C while that timer is active and has not expired, the new programmed value will be ignored until the timer expires and/or is reset by MR. The MR input has an internal pull-up to BAT.