Group 4 Craig Bellamy Jeremy Ruple Frank Swehosky Ryan VanAlstine

Introduction The Internet is capable of wide- scale multimedia streaming Current analog streaming are limited to range, ex. t.v., FM radio We propose to create an Internet Radio player

Original Objectives and Deliverables Connect to a remote server via TCP/IP Receive streaming audio Decode the streaming audio Convert a digital signal into an analog signal Output the analog signal to a line out Scanning functionality Preset and programmable buttons Final product: a functional web radio player

Background Multimedia Technology Multimedia Streaming TCP/IP Embedded System

Approaching the Problem Research uClinux Software Scanning functionality Downloading mp3 data Decoding mp3 data

Approaching the Problem cont. Hardware DAC/Speakers LCD Button interface Integration Software integration Device drivers

Coldfire Board What it provides: 8 MB RAM 1 MB Flash ROM NE2000 compatible Ethernet interface 2 serial connections, 1 for Terminal 1 16 bit general purpose parallel I/O port

uClinux The Linux/Microcontroller project is a port of the Linux 2.0 to systems without a Memory Management Unit At present, only Motorola MC68000 derivatives are supported NFS and SMB file-systems can be mounted

uClinux-negative cont. no fork() - use vfork(), check semantics still OK. limited libc - either add more to libc, or remove some functionality. binary size - currently exec() loader can't handle things bigger than 128k. This can be extended by hacking the linux/mmnommu code, grep for BIGALLOCS.

Software Design

Scanning Broadcasting Sites Use a packet sniffer? Security risks Difficult implementation Use Shoutcast’s web page! Contains mp3 broadcasting sites Download contents of page Parse page Store into an array

Downloading MP3 Data Connect to the site (tcp connection) Issue command to send Receive data into buffers Store buffers into a file

Decoding the MP3 Data Input the MP3 file that was downloaded Use Huffman’s Algorithm to decode it minimal variable-length encoding based on the frequency of each character Output the decoded data to the DAC

DAC Driver purpose of the DAC driver is to allow data in memory to be sent to the physical DAC via a programmable port accepts a buffer of data and a given frequency, and will output one 16 bit value at each period to the physical DAC data has to be sent to the physical DAC one bit at a time

Original Timeline Componen t Install Software XS Network Interface XXTP Digital-to- Audio XXTR MP3 Decoding XXTI RCA line out, Speakers XTN Integration of hardware XGTT LCD Interface XT Button Interface BXXT Net Scan RXXT Integration of System EXX Testing ATTT Final Presentation KX

Modified Timeline Component Install Linux in ROM SX Connect to Website & Download MP3 data PXXT MP3 Decoding RXXT Scanning Algorithm IXXT Button & LCD Interface NXXT DAC and LCD Drivers GXXT Integration of All Hardware BXX Integration of Whole System RXXX Testing ETTT Final Presentation AXX K

Accomplishments Connect to a remote server via TCP/IP Receive streaming audio Decode the streaming audio Convert a digital signal to an analog signal Output the analog signal to a line out Scanning functionality Preset and programmable buttons X Final product: a functional web radio player X

Current Problems Limited commands with uClinux Integration of software and hardware DAC device driver Passing data between programs Size of the ROM 1 MB ROM vs. 3.6 MB kernel Unreliable Coldfire board

QUESTIONS ?