The Lake County court dismissed more serious charges of aggravated battery.
Richmond, who left the University of Illinois after his freshman season in an unsuccessful attempt to be drafted by a professional team, had been accused of punching his ex-girlfriend and threatening her family with a gun.
Defense attorney Lawrence Wade said Richmond never wielded the gun, but bore some legal responsibility for it because it had been in his car.
It's not clear how the resolution will affect Richmond's quest to make it in the NBA.
The court had denied his previous requests to travel to player-organized minicamps, and Wade said probationers need the approval of their probation officers to leave the state.