First and foremost, the firmware generates the PWM signal to the 8 outputs of a port. The control values are provided over the serial interface. In parallel, the firmware digitizes analog values periodically and sends them on to the PC. The tacho signal is also processed. Up to 8 temperature and 8 tachometer values per second can be transmitted. The status LED’s and the alarm sounder can also be controlled from the PC. In addition, the firmware can respond to requests of the Plug n ‚Play enumerator.
Fan controller in device manager