Some C programming.

Answer all of these or one. Thanks!

All Interrupt Service Routines with the exception of SysTick_Handler must do this: i. Explicitly pop the SP before returning from the interrupt ii. Not use the Stack iii. Write to a FIFO iv Explicitly acknowledge the Interrupt v. Write to a mailbox vi. None of the above Write comments for even line of the following code and declare the variable's value: int x = 1, y = 2, x[10]; int *ip; ip = &x; y = *ip; *ip = 0; ip = &z[2]; From the Valvano's book examples explain the meaning of the following statement: #define PF2 (*((volatile unsigned long *)0x40025010)) Write a subroutine that copies string s to string t (both are null-terminated) using pointer arithmetic