Abstract: An embodiment includes retrieving performance monitor data from an I/O processor. A performance monitoring driver coupled to a performance monitoring unit may be registered as a private driver with a real time operating system of the I/O processor. Events within the I/O processor may be selected on which to gather data. The selected events may be sent as a message request to the real time operating system. The message request may be translated into the appropriate parameters based on a set of private group parameters that may be accessible by the real time operating system. The message request may be sent as a translated request to the performance monitoring unit. The pieces of data requested by the translated request may be returned to the performance monitoring driver. The pieces of data then may be sent to a location specified in the message request.

Abstract: A unique speakerphone for celluar telephones includes in the transmit audio path between microphone 112 and transmitter 118, a transmitter mute switch which disconnects the audio path to the transmitter from the microphone 112, and a transamit gain amplifier that is controlled to lower the feedback the microphone can pickup from the speaker 110. In the feedback path to the radiotelephone receiver 120 from the cellular base station 122 and the land line telephone system 124, the speakerphone includes the controlled amplifier 106 which is fed into the speaker mute gate, and the speaker 110 to close the feedback loop. De-emphasized audio is sampled by the A/D 102 on both the microphone-to-transmittr side of the loop and the receiver-to-speaker side of the loop. The microcomputer 104 is able to detect and eliminate howl, as well as determine whether howl exists, from the A/D sampling.