CDR- Digital Audio Recorder/Player

Brian Cowdrey

Mike Ingoldby

Gaurav Raje

Jeff Swetnam

Objectives

Successfully encode/decode MP3

Play/Stop a song

Select track and fast forward/rewind

Read off from Compact Flash Card

Display song title and time

Voice Recording in MP3 Format

Equalizer Controls

Hardware Overview

Micro-Processor

4-way switch

Buttons

LED’s

Volume CtrlUSB

JTAG

External RAM

MP3

CF Card

Mic

HeadPhoneJack

LCD

Contrast Adj

I2C

Software OverviewInterrupts Drivers User Interface

MP3 sync

User Inputs

LCD

Button Get

FAT-16CF

MP3 Send Data

USB

LCD Draw

Button Response

File/FolderControl

Play Back Control

Schematic

MP3 Schematic

Microprocessor(C8051F320)

MicroprocessorOnly General I/O - no Addr/Data bus

Implement Addr/Data bus with latchesAllow us to have external memoryMemory map I/O devices

Mp3 decoder/encoderCF cardExternal RAMLCD

25MHz -> 40ns per cycle

I2C Bus

I2C bus is a standard serial bus

Gives commands to MP3 chip

2-wire interfaceClockData

Used for the LCD

Still only 2-wireClockData

Has no Start/Stop/Ack bit like I2C

Transmits only 8-bits directly

Custom Serial Bus

Compact Flash Card

Uses new Addr/Data Bus

Memory mapped and interfaced using 8 separate registers on the card

We have FAT-16 code developed to be used on a CF card from a previous project

RS-232 Interface

Abandoned!!!Can download code updates over the

JTAG interface Interact with the computer over the USB

portCan single step the processor over JTAG

JTAG implemented on processor

MP3 Encoder/Decoder(MAS 3587F)

MP3 Encoder/Decoder

No playback controlVolume, file select, and other processes

are controlled by micro-processor

Encoding/decoding is always activePlayback occurs whenever there is an

input and the proper application is selected

Option to load additional programsSC4 speech codec

Encoder Signal Flow

D0 and D1 Ram banks Reserved sections for application control Input/output specification

PIO Timing Diagram for Decoding

PIO Timing Diagram for Encoding

LCD/User Interface

Monochromatic graphical 122 x 32 pixel format

8-bit interface with built- in controller

Display song title, play time and menu

LCD Block Diagram

LCD Timing Diagram

LCD Code

Generate code to display characters

Write functions such as draw line, draw square, and fill

Go to X,Y

LCD Driver Code

USB

USB Communication Flow

Pipe BundlesMoves data

between host software and device endpoint

EndpointsOne directional

data flow

Software Model

Client SW

Driver

Client SoftwareGUI for Users

DriverGrants access to bus

FirmwareInteracts with hardware on board

MP3 Software Higher level code

Firmware

MP3 Software

Project Schedule

Division of Labor

Jeff MP3 encoder/decoder Signal processing

Brian LCD User interface

Mike Microprocessor Compact Flash

Gaurav USB

Parts List

PCB 8-bit LatchesMP De-MuxUSB Port LED/Resis/CapMP3 Chip Power Reg.CF Socket Power DiodeLCD Misc. ButtonsMic JTAG connectorHP Jack LCD Pot.Ext. RAM

Parts