NBA Basketball is a multiplayer sports video game produced by Mattel and released for its Intellivision video game system in 1980. The players each control a basketball team competing in four timed quarters of game play. While Mattel did obtain a license from the National Basketball Association and used the NBA logo in its box art, NBA Basketball does not use any official team or player names.
Each player controls a three-man basketball team, actively controlling one team member at a time, with the computer controlling the other two. Like the real game of basketball, the player's team must score more points than the opponent's team by shooting more baskets and blocking opponent's shots on their basket. The game consists of four quarters, each a simulated twelve minutes in length. The pace of the game is governed by a simulated 24-second shot clock.
At the start of the quarter, the two players control the centers during the tip-off. The team who wins the tip-off begins on offense, with the player controlling the team member with the ball. Players on offense use the keypad to select where in the offensive half of the court they wish to pass the ball. If a computer-controlled offensive team member receives the pass, control passes to that team member. When attempting to shoot the ball at the basket, players may choose between a jump shot (which is less likely to be blocked, but only hits at close range) and a set shot (which can hit from long distances, but has a greater chance of being blocked).
On defense, the player controls one member of the team, considered the "captain." The defense can block shots, intercept passes and rebound missed shots, and computer-controlled defensive team members are able to steal the ball from the offense. When a defensive team member (either player- or computer-controlled) gets the ball, the player controls that team member and switches to the offensive controls.
If the score is tied at the end of the fourth quarter of play, a single five-minute overtime period is played.
Source: Wikipedia, "Basketball (Intellivision game)", available under the CC-BY-SA License.