This routine provides a game with the means for allowing the player to choose the game number he would like to play, and the number of players. The game indicates the number of game versions available, by placing the value in the B register. The number of players allowed is specified in the A register. If a parameter is passed in with a value of 0, then the corresponding question will not be asked. The number of players selected is returned in $C879, while the game number selected is returned in $C87A.
This routine performs most of the work involved in allowing the player to select a game version and the number of players. It displays the game # and player options, and allows the player a certain amount of time to modify their values. Anytime one of the buttons is used to modify a value, the timer will be restarted. When a button is pressed, the associated value is modified, and then redisplayed on the screen. This routine will return when either the timer expires, or button 4 is pressed.
A-reg = maximum number of players allowed
B-reg = number of game versions available
DP = $C8
$C879 contains number of players selected
$C87A contains the game version selected
D-reg, X-reg, Y-reg trashed