A DSP-based decompressor unit for high-fidelity
MPEG-Audio over TCP/IP networksA DSP-based decompressor unit for high-fidelity
MPEG-Audio over TCP/IP networksCopyright 1997 by Bj?n Wes? at Axis Communications AB, Sweden
[ Home | Contents | Component and tool archive ]
This page contains spec-sheets, litterature and tool-links related to the project. Most files are in Adobe Acrobat format.
The DSP that does all the decoding work. The C31 is a 32-bit floating-point DSP from Texas Instruments, and is a member of the C3x family. The C32 is cheaper but has less memory than the C31, so for this prototype the C31 was chosen for simpleness of design. The speed chosen is 60Mhz, which gives an internal maximal instruction execution speed of 30 MIPS.
By: Texas Instruments Distribution: External Formats: PDF Retailer: Jakob Hatteland, 08-445 75 00, Marie Nystr?
PCM1721 stereo 16-bit D/A-converter
This is the data-sheet for the dual 16-bit CD-quality D/A used in this project. The actual component in the prototype is the PCM1723 which has no datasheet yet - it's specifications are identical though. The D/A has a serial input port that accepts samples from the DSP's serial port. The D/A also features a PLL that can generate the sample-clocks from a 27MHz crystal source.
By: Burr-Brown Distribution: External Formats: PDF Retailer: Bexab Sweden AB, Lars ?erg
MCM6206B 32k * 8 bit fast SRAM
To make the decoder simple, external RAM is used. The exact part type is a Toshiba or UMC part, but they are compatible with this Motorola part. The part speed used is 15ns. The DSP has a 32-bit databus, so 4 SRAM chips are used in parallel.
By: Motorola Distribution: External Formats: PDF Retailer: In-house stock
TDA1518BQ 2x12W Stereo Power Amplifier
An integrated power amplifier is used to directly hook up two speakers to the system. The TDA1518BQ requires almost no external components and operates from a single powersupply of 6-18 volts.
By: Philips Distribution: External Formats: PDF Retailer: ELFA
The development software used is not available inside the report, but below are links to the archives that hopefully still contain these tools (or newer versions of them):
These files are a port of GCC (and the binary ultilities gas, ar, ld, nm, size, objdump, etc.) for the TMS320C[34]x DSP family. It was done by Dr. Michael P. Hayes. I compiled and worked with these under Linux, but they should work under other unixes as well.
Texas Instruments has a very good DSP evaluation kit, including an assembler and debugger, for $99 or similar low price. For code development in this thesis, before my own board was manufactured, I used this kit along with a wirewrapped memory expansion module.
This document may be freely distributed for educational purposes. See the copyright notice for additional information.