The prompt module is responsible for triggering ASR. It has a separate thread that monitors the PPS control object for changes and then triggers a recognition turn based on those changes. On an initial prompt (a new recognition turn), the prompt module plays a voice prompt that asks the user for a command. On subsequent turns within the same session, the prompts may take different forms depending on what's required. For example, if the command wasn't understood, a voice prompt asks for the command to be repeated. For media playback, there may be a spoken confirmation as well as a visual change to the HMI to indicate that playback is starting.
The prompts that are rendered for various situtuations are defined by the prompt configuration files, *prompts.cfg. These files reside at various locations in the ASR subsystem depending on their purpose.
The prompts to be rendered for the various conversation modules are defined in car-prompts.cfg or prompts.cfg files in the ${QNX_TARGET}/opt/asr/conversation/locale/module directory. For example, the English prompts for media playback are in the ${QNX_TARGET}/opt/asr/conversation/en-US/car-media directory
The prompt module is tightly integrated with the HMI and the audio drivers. You should be able to adjust the prompt module to suit your needs just by modifying the configuration files. If you need more extensive changes, please contact QNX technical support.