| 摘要 |
A computer peripheral offers a number of operational modes. The peripheral device may be a position input device, such as a digital joystick, capable of operating in a digital transmission mode or an analog emulation mode. A command sequence emulator permits the user to define a button on the peripheral corresponding to a user-selected keyboard command sequence. Activation of the selected peripheral button is detected and initiates a command sequence emulation of keyboard command sequences stored in a database in association with the peripheral button. The emulator places the first command from the command sequence in a keyboard register within the computer. The emulator subsequently generates a keyboard input interrupt causing the computer to read the keyboard input port containing the first command. The process is repeated for each command in the command sequence. In the digital transmission mode, the digital joystick generates and transmits digital position data to the computer via a digital port. However, the digital joystick has an analog emulation mode to permit older software to function as if coupled to a conventional analog joystick. The digital joystick emulates resistances to provide an indication of joystick position. The digital joystick calculates digital position data and converts it to emulation resistance data for transmission to the gameport. The digital joystick is capable of bidirectional communication using the gameport. The gameport includes one or more timers whose inputs are coupled to resistances within the digital joystick. Output instructions to the gameport cause a reset to the timer, which is detected within the joystick. The detected changes in the timer inputs are used as interrupts to a microprocessor within the joystick. These are interpreted as one or more commands. |
