SPRUI30H November 2015 – May 2024 DRA745 , DRA746 , DRA750 , DRA756
The keyboard controller external interface pins map on the device pads when the device IO cells are configured and multiplexed for the keypad function by the control module. For more information, see Pad Configuration Registers, and Section 27.2.1, General-Purpose Interface as a Keyboard interface.
The external keypad typically connects directly to the keyboard controller of the device (see Figure 28-2).
To acheive the configuration shown in Figure 28-2 software needs to reconfigure the internal pulls on the kbd_* pads appropriately. The settings of those pads default to pull down resistors selected, software must reconfigure to pull ups on rows and to disable the pulls on columns.