Digital Signal Processing Device Arbitrary Audio Delay Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing digital signal processing devices using burst transfer in DRAM are limited to achieving delays that are multiples of the burst length, making it difficult to achieve arbitrary sampling period delays, which limits the quality of audio effects like reverb.
Innovation Solution
A digital signal processing device with a DRAM that burst transfers audio data and a buffer memory capable of accumulating twice the burst length, allowing for control of delay lengths by writing audio data one word at a time from arbitrary addresses and alternately transferring burst length data between two buffer memory areas to achieve delays shorter than the burst length.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If burst transfer is used to transfer audio data in DRAM, then transfer efficiency is improved, but delay length is restricted to multiples of burst length
Solution Approach 1:
The buffer memory is divided into two distinct areas: a first area for accumulating audio data and a second area for storing delay data. This segmentation allows independent control of data flow paths, enabling arbitrary delay lengths by selectively transferring data between these segmented regions rather than being constrained by the burst transfer mechanism alone.
Solution Approach 2:
The buffer memory acts as an intermediary between the audio data source and the DRAM. By introducing this intermediate storage layer with specific addressing control, the system can achieve arbitrary delay lengths. The buffer memory receives audio data and selectively transfers portions of it to DRAM with controllable delay, overcoming the burst length limitation.
2Adaptability or versatility
If delay is achieved by burst transfer, then delay time is limited to multiples of burst length, but implementing arbitrary delay requires more complex control mechanisms
Solution Approach 1:
Audio data is preliminarily accumulated in the buffer memory's first area before being transferred to the second area or DRAM. This preliminary accumulation phase allows the system to prepare data in advance and then transfer it with precise delay control, achieving arbitrary delay lengths through the timing of the transfer operation rather than complex continuous control.
Solution Approach 2:
The system dynamically switches between different data transfer modes: accumulating data in the buffer memory, transferring burst data to DRAM, and controlling delay lengths by managing the timing and addressing of these transfers. This dynamic control of the buffer memory operations enables flexible delay lengths without requiring fundamentally complex hardware architecture.
Data Source
AI summary
A digital signal processing device includes a control unit that performs control to alternately burst transfer burst length audio data in a first half area of a first buffer memory and burst length audio data in a second half area of the first buffer memory to a DRAM, in which the control unit performs control to burst transfer the burst length audio data in the first half area of the first buffer memory to the DRAM while writing audio data one word at a time to the second half area of the first buffer memory in sequence and performs control to burst transfer the burst length audio data in the second half area of the first buffer memory to the DRAM while writing audio data one word at a time to the first half area of the first buffer memory in sequence.