Patent ID: 6125139
Filing Date: 2000-09-26
Classification: G06F,H04M

Abstract:
A digital cordless telecommunications unit for receiving analog receive voice signals and transmitting analog transmit voice signals and for transmitting digital baseband transmit signals and receiving digital baseband receive signals, comprising:(a) an audio functions circuit, comprising:(i) an audio front end circuit;(ii) an adaptive differential pulse code modulator (ADPCM) codec connected to the audio front end circuit;(iii) a FIFO buffer coupled to the codec adapted for storage of data words received from an external device and output of the data words to the codec, the FIFO buffer including means for determining if there is overflow of data words in the buffer and means for discarding a data word from the buffer in response to the overflow, and thereby avoiding a disruption of synchronous communication;(b) a systems control functions circuit, comprising:(i) a microcontroller;(ii) a memory accessible by the microcontroller;(iii) an interrupt controller connected to the microcontroller;(iv) parallel ports connected to the interrupt controller;(v) a wake-up timer connected to the interrupt controller;(vi) a reset circuit;(vii) a clock generator connected to the microcontroller; and(c) a protocol functions circuit comprising a frame formatter for determining and extracting digital receive voice signals and digital receive control signals from the digital baseband receive signals and combining digital transmit voice signals and digital transmit control signals to form the digital baseband transmit signals.