There are differences between the dsPIC33 flash and dsPIC30 flash. For one thing, the dsPIC33 flash programs and erases faster than the dsPIC30 flash. The endurance of the dsPIC30 flash is greater than the endurance of the dsPIC33 flash. The dsPIC33 flash is rated for 1000 program/erase cycles. When porting programming code from a dsPIC30 system to a dsPIC33 system, the array organization is slightly different and some of the programming command codes are different.