The differences between the Black Codes (1800-1866) - which by the way were a part of life both north and south - were 1. method of inception, 2. degree of severity, and 3. degree of participation.
The Black Codes were ways that whites dealt with blacks. They weren't pretty and they weren't fair but they weren't generally cruel. As I said, they were incorporated in communities both north and south - but far more pervasive in the south.
Jim Crow laws came as a result or a reaction to the imposition of reconstruction. One of the very first things southerners did when they regained control of their state legislatures was to pass laws severely restricting the civil rights of blacks. They were exclusive to the south. They were universally applied throughout the south. They affected virtually every part of life. Some of the Jim Crow laws that differed from Black Code laws included:
The Dixiecrats also passed gun control laws specifically designed to keep guns out of the hands of newly freed black slaves so the KKK could more easily kill them. It went on this way until 1872 when some ex-Union Army soldiers and officers formed an organization called “The National Rifle Association’’ and at risk to themselves gave blacks guns and the knowledge to use them so to protect themselves from Klan violence.