MP3 NG: A Next Generation Consumer Platform

R

Like the IRDA controller, an interrupt is generated every time the FIFOs transfer their last word into the shift registers. Assuming a 48 kHz audio sampling rate, this will result in an interrupt every 83.3 s. To put this in perspective, this means that the CPU will get an interrupt every 5,333 instructions.

Table 6: Audio DAC Interface Signal Summary

Signal

Type

Description

 

 

 

DAC_MCLK

Output

Master clock

 

 

 

DAC_LRCK

Output

Left / Right clock, determines which channel is currently being

 

 

transferred

 

 

 

DAC_SDATA

Output

Serial audio data

 

 

 

DAC_SCL

Output

I2C data clock

DAC_SDA

I/O

I2C data

Touch Screen Interface

The touch screen interface is an I/O port that lets the processor read the data returned by a two-channel analog-to-digital converter. This lets the system software read the X and Y coordinate resistance values that result from the user touching the screen. The system software handles linearization and filters out transient touch events. (See Figure 23 and Table 7.)

 

Register

32

D

3

D_IN[31:0]

Q

32

 

 

D_OUT[31:0]

 

 

AD_SCK

AD_SDI AD_SDO

Figure 23: Touch Interface Block Diagram

Table 7: Touch Screen Interface Signal Summary

Signal

Type

Description

 

 

 

AD_SCK

Output

Serial data clock

 

 

 

AD_SDI

Input

Serial data in

 

 

 

AD_SDO

Output

Serial data out

 

 

 

24

www.xilinx.com

XAPP169 (v1.0) November 24, 1999

 

1-800-255-7778

 

Page 24
Image 24
Xilinx XAPP169 manual Touch Screen Interface, Audio DAC Interface Signal Summary Type Description

XAPP169 specifications

Xilinx XAPP169 is a pioneering application note that delves into the design and implementation of high-performance digital signal processing (DSP) systems. It serves as a reference guide for engineers and designers looking to leverage Xilinx Field Programmable Gate Arrays (FPGAs) for sophisticated DSP applications. The document provides a comprehensive overview of the techniques and methodologies necessary to harness the power and flexibility of FPGA technology in DSP design.

One of the main features of XAPP169 is its focus on the integration of various DSP functions, including filtering, modulation, and Fourier transforms. By utilizing the inherent parallelism of FPGAs, designers can achieve significant performance enhancements compared to traditional DSP implementations. This parallel processing capability allows for real-time processing of high-bandwidth signals, making XAPP169 ideal for applications such as telecommunications, aerospace, and medical imaging.

The application note emphasizes the use of Xilinx’s advanced tools and libraries, such as the Xilinx System Generator for DSP and the Xilinx Vivado Design Suite. These tools facilitate the modeling, simulation, and synthesis of DSP algorithms tailored to specific requirements, enabling a rapid development cycle. By providing pre-optimized building blocks and IP cores, XAPP169 streamlines the design process, reducing time-to-market for new products and innovations.

Additionally, XAPP169 highlights the ability to leverage high-speed serial transceivers present in Xilinx FPGAs. These transceivers enable reliable transmission of data across long distances with minimized latency and optimized bandwidth utilization. The application note outlines various techniques for managing signal integrity and maximizing throughput, ensuring that designs can meet the stringent requirements of modern DSP applications.

Another characteristic of XAPP169 is its attention to resource utilization and optimization strategies. The document discusses how to balance performance with area and power consumption, which is crucial in embedded applications where space and power are at a premium. By employing advanced synthesis strategies and leveraging the capabilities of Xilinx’s architecture, designers can create efficient and scalable DSP systems.

In summary, Xilinx XAPP169 serves as an invaluable resource for engineers seeking to harness the capabilities of FPGAs in DSP applications. With its focus on high-performance design, integration of advanced tools, and optimization strategies, it opens up new possibilities for innovation in various fields where digital signal processing is essential.