Abstract: A method and apparatus of managing data stream, the method comprising archiving received data in a circular buffer; utilizing a breakpoint in realizing the archived received data continuity, wherein the breakpoint is set to the last data portion of the archived received data; when the archiving of the received data approaches the end of the circular buffer, stitching the last portion of the archived received data to the start of the circular buffer; and setting the breakpoint to the updated last data portion of the archived data.

Abstract: A data processing device is provided with an indexed-immediate addressing mode for processing streams of data. An instruction register 900 receives an instruction for execution. Decoding circuitry 913 selects a register specified by a field in an instruction to provide an index value. An immediate field from the instruction is combined with the index value by multiplexor 910 to form an address which can be used to access a data value or to form a target address for a branch instruction. Mux control 915 parses the immediate value to determine how to combine the immediate value and the index value.

Abstract: A data processing device uses a portion of a random access memory as an input buffer for holding a portion of a stream of data which is being processed by a processing unit within the processing device. Various break-point source tasks 801a–n determine discontinuities in the portion of data stored in the input buffer and a sorted list of the addresses of the discontinuities is maintained in breakpoint queue 800. Since the buffer is managed in a FIFO manner, a single breakpoint register 810 is sufficient to monitor addresses as they are provided by an address register 820 for accessing the random access memory. When a breakpoint is detected, the breakpoint queue and the breakpoint register is updated by an update task 802.

Abstract: A data processing device is provided with an indexed-immediate addressing mode for processing streams of data. An instruction register 900 receives an instruction for execution. Decoding circuitry 913 selects a register specified by a field in an instruction to provide an index value. An immediate field from the instruction is combined with the index value by multiplexor 910 to form an address which can be used to access a data value or to form a target address for a branch instruction. Mux control 915 parses the immediate value to determine how to combine the immediate value and the index value.

Abstract: A data processing device uses a portion of a random access memory as an output buffer for holding a frame of PCM sample data which is being output after being processed by a processing unit within the processing device. Fine grained synchronization between a reference clock and a stream of PCM data frames is provided by transferring only a portion of selected frame of PCM sample data PCM(n+1), in response to a time difference 971. A breakpoint address is determined to delineate the portion of the selected frame that is to be transferred. A sorted list of the addresses of the discontinuities is maintained in breakpoint queue. Since the buffer is managed in a FIFO manner, a single breakpoint register is sufficient to monitor addresses as they are provided by an address register for accessing the random access memory. When a breakpoint is detected, the breakpoint queue and the breakpoint register is updated by an update task 802.

Abstract: A data processing device uses a portion of a random access memory as an output buffer for holding a frame of PCM sample data which is being output after being processed by a processing unit within the processing device. Fine grained synchronization between a reference clock and a stream of PCM data frames is provided by transferring only a portion of selected frame of PCM sample data PCM(n+1), in response to a time difference 971. A breakpoint address is determined to delineate the portion of the selected frame that is to be transferred. A sorted list of the addresses of the discontinuities is maintained in breakpoint queue. Since the buffer is managed in a FIFO manner, a single breakpoint register is sufficient to monitor addresses as they are provided by an address register for accessing the random access memory. When a breakpoint is detected, the breakpoint queue and the breakpoint register is updated by an update task 802.

Abstract: A data processing device is provided with an indexed-immediate addressing mode for processing streams of data. An instruction register 900 receives an instruction for execution. Decoding circuitry 913 selects a register specified by a field in an instruction to provide an index value. An immediate field from the instruction is combined with the index value by multiplexor 910 to form an address which can be used to access a data value or to form a target address for a branch instruction. Mux control 915 parses the immediate value to determine how to combine the immediate value and the index value.

Abstract: A data processing device is provided which has multiprocessors that can be configured on a cycle by cycle basis as loosely coupled or tightly coupled. Bit-stream Processing Unit (BPU) 110 executes instructions from ROM 112 and accesses data from RAM 111. Similarly, Arithmetic Unit (AU) 120 executes instructions from ROM 122 and accesses data from RAM 121. Both processor operate in parallel and exchange data by accessing RAM 121. AU 120 can receive an instruction directive from BPU 110 directing it to perform a selected sequence of instructions in a loosely coupled manner. AU 120 can also receive an instruction directive from BPU 110 directing that a portion of AU 120 operationally replace a portion of BPU 110 for the duration of one instruction which allows data to be passed directly between the processors in a tightly coupled manner.

Abstract: A data processing device uses a portion of a random access memory as an input buffer for holding a portion of a stream of data which is being processed by a processing unit within the processing device. Various break-point source tasks 801a-n determine discontinuities in the portion of data stored in the input buffer and a sorted list of the addresses of the discontinuities is maintained in breakpoint queue 800. Since the buffer is managed in a FIFO manner, a single breakpoint register 810 is sufficient to monitor addresses as they are provided by an address register 820 for accessing the random access memory. When a breakpoint is detected, the breakpoint queue and the breakpoint register is updated by an update task 802.

Abstract: A data processing device is programmed to decode and transform a stream of data representing a plurality of subband encoded channels of audio data into one or more channels of PCM encoded data for reproduction by a speaker subsystem. An improved method for decoding and transforming utilizes downmix matrices (1021 and 1022) to form downmixed frequency domain channels in buffers (1031-1034). Only two long DCT transform operations (1041 and 1042) and two short DCT transform operations (1043 and 1044) are needed to transform the downmixed frequency domain channels into a left PCM output (1071) and a right PCM output (1072).

Abstract: A data processing device 100 uses a portion of a random access memory 111 as an input buffer for holding a portion of a stream of data which is received by an input interface 130. Likewise, a portion of a memory 121 is used as an output buffer for holding a portion of processed data which is output by an output interface 140. A processing unit 110 within the processing device manages the flow of input and output data. The input interface asserts an I/O request 860 when it receives a data word, and the output interface asserts an I/O request 870 when it needs a data word. In response to an I/O request, fast interrupt circuitry inserts a ghost instruction which is formed by doppelganger circuitry into an instruction sequence which is being accessed from a ROM 112. The ghost instruction performs the requested data transfer.

Abstract: A data processing device uses a portion of random access memory 121 as an output buffer 124 for holding a portion of a stream of PCM data which is to be output to a digital to analog converter 530. D/A 530 forms a left analog channel and a right analog channel for speaker subsystems 814 and 815. The PCM data stream is stored in the output buffer so that PCM data samples which pertain to the left channel are stored at even address and PCM data samples which pertain to the right channel are stored at odd address. Control circuitry 145 monitors direct memory access (DMA) transfers which transfer PCM data samples to PCM serializer 142. By comparing the address of each DMA transfer to a left/right channel signal from the D/A, the control circuitry can verify that channel synchronization is correct. If a synchronization error is detected, an channel synchronization error correction procedure is invoked.

Abstract: A data processing device uses a portion of a random access memory as an input buffer 114 for holding a portion of a stream of data which is being processed by a processing unit within the processing device. A Get Bit-Field instruction is provided which directs the processing unit to extract selected bit fields from the data stream stored in the input buffer. A register R6 holds a bit address which points to the end of a selected bit field, while a register R0 holds the width of the selected bit field. An address register is connected to a register R6 in a manner that allows data words to be accessed in input buffer 114 using only a word portion of the bit address. A funnel shifter 203 is disposed to extract the selected bit field from concatenated data words in response to a bit address portion of the bit address in register R6.