Windows communicates with joystick device drivers through messages it sends to the driver. The driver process these messages with its DriverProc entry-point function.
A message consists of three parts: a message number and two LONG parameters. Message numbers are identified by predefined message names. The two LONG parameters contain message-dependent values.
This section contains an alphabetical list of all messages that can be received and sent by joystick drivers. Each joystick message has the JDD_ prefix.