Abstract: A Heating, Ventilation, and Air Conditioning (HVAC) system that is configured to receive a refrigerant from a condenser at a fixed expansion device and a variable expansion device. The system is further configured to output a first portion of the refrigerant to a first downstream HVAC component at a fixed flow rate using the fixed expansion device. The system is further configured to apply a first force to a pin of the variable expansion device based on a sensed temperature. The system is further configured to apply a second force to a valve of the variable expansion device via the force applied to the pin and to output a second portion of the refrigerant to a second downstream HVAC component at a variable flow rate based on the second force using the valve of the variable expansion device.

Abstract: A near full duplex portable handset speakerphone comprises: a microprocessor; a hands-free receive register connected to the microprocessor; a hands-free transmit register connected to the microprocessor; a ROM having a speakerphone operation algorithm, the ROM-connected to the microprocessor; a first analog-to-digital converter connected to the hands-free receive register; a second analog-to-digital converter connected to the hands-free transmit register; a first programmable digital attenuator connected to the microprocessor and to a speaker; and a second programmable digital attenuator connected to the microprocessor and to a microphone, wherein near full duplex communication is achieved without digital signal processing. In another feature of the invention, the hands-free registers provide a digital representation of the speech volume in each direction to the microprocessor.

Abstract: A device and method for providing inter-processor communication in a multi-processor architecture. A post office RAM has a plurality of mailboxes. Each mailbox is write-accessible by one port, but is read-accessible by the other ports. Thus, a processor device on a port has write-access to one mailbox, but can read the other mailboxes in the post office. A transmitting processor communicates with a receiving processor, by utilizing the post office. The transmitting processor writes information into its own mailbox, and signals a receiving processor. The receiving processor determines which of the processor devices signalled it, and reads the information in the transmitting processor's mailbox.