The following are defined:

  #define PD2 2U

  #define PD4 4U

  #define PD7 7U

  #define BIT( x )  (1U<<(x))

In this and the next question, write C statements that would enable PD2, PD4 and PD7 to be edge triggered on the rising edge.

For this part of the question, write a C statement for the GPIOIS register (GPIOD->IS) that would accomplish the above. 

GPIOD->IS &= ~xxxxxxxxxxxxxxxx; or GPIOD->IS |= xxxxxxxxxxxxxxxx; // do not leave spaces for the xxxxxxxxxxxxxxx, e.g. (BIT(PD2)|BIT(PD4)).