What was the goal of the black codes?

The Black Codes aimed to limit the freedom of African Americans as a way to ensure they continued a cheap labor force after slavery was abolished.

This way, Black Codes prohibited blacks from holding occupation other than farmers, gave penalties for vagrancy, limited the right to buy and own property, marry, make contracts, testify in court, limited the property that blacks could own, restricted labor contract laws and others.

Explanation:

The Black Codes were a series of laws that were passed mostly in the Southern States that limited the liberty of ex-slaves and African Americans.

When slavery was abolished, ex-slaves and African Americans were considered American citizens with the same rights as any other.

When Andrew Johnson reached the presidency he lost control of Reconstruction and made possible for southern states to create the Black Codes.