In-Application Programming is where the user can program the Flash from an application running in RAM. This is done by setting up a couple of pointers and then calling in an application programming routine to pass these pointers as parameters. The first pointer points to the command array that will be processed. If there are multiple command bytes that need to be passed to the calling routine, then these Bytes can be sent on by just passing the pointer to the beginning of these commands. That gets placed in R0. Then, R1 contains a pointer to where we are going to put the result array. There can be a number of Bytes of result. That can be placed in an array starting at the address that's pointed to by R1.