I pod new

iPOD – Using Microcontroller (AtMega162)

--Abhi

MP3 PLAYER- AN ENGINEER’S PERSPECTIVE

The main idea behind a Microcontroller based MP3 player is to develop a MP3 player by using Atmega microcontroller and SD card. Basically, MP3 is the format used for storing audio files, which is a type of compression. Initially MP3 files are stored onto the SD card and are played using a micro controller which is connected to a keypad and an LCD display. Users can operate this MP3 player using the keypad and select songs that are stored on the MP3 player.

COMPONENTS USED• Atmega 162 Microcontroller• LCD Display• Voltage supply/Power source• DSP Processor• Connecting wires• Software used: Eagle, AVRDUDESS, Programmer’s

Notepad, Eclipse, Android Development Tool• USBASP

Mp3 player in making!

AtMega-162• The high-performance, low-power Atmel 8-bit AVR RISC-

based microcontroller combines 16KB of programmable flash memory, 1KB SRAM, 512B EEPROM, and a JTAG interface for on-chip debugging. The device supports throughput of 16 MIPS at 16MHz and operates between 2.7-5.5 volts.

• By executing instructions in a single clock cycle, the device achieves throughputs approaching 1 MIPS per MHz, balancing power consumption and processing speed.

The data sheet of AtMega-162 Microcontroller is being attached below:

Atmega 162 – Key features

Assembled circuit

• High-performance, Low-power AVR 8-bit Microcontroller• Advanced RISC Architecture– 131 Powerful Instructions – Most Single-clock Cycle Execution– 32 x 8 General Purpose Working Registers– Up to 16 MIPS Throughput at 16 MHz– On-chip 2-cycle Multiplier• High Endurance Non-volatile Memory segments– 16K Bytes of In-System Self-programmable Flash program memory– 512 Bytes EEPROM– 1K Bytes Internal SRAM– Write/Erase cycles: 10,000 Flash/100,000 EEPROM– Optional Boot Code Section with Independent Lock BitsIn-System Programming by On-chip Boot ProgramTrue Read-While-Write Operation– Up to 64K Bytes Optional External Memory Space– Programming Lock for Software Security• JTAG (IEEE std. 1149.1 Compliant) Interface

AtMega 162 Data Sheet

USBASP• These AVR programmers are based on the USBasp design and connect to your computer's

USB port. Not only are they quite compact (70x20mm), but the design is really elegant. The USB interface is achieved by using an atmega8 processor and the rest is done in firmware.

• In order to load the USBASP firmware onto the AtMega8 on the programmer, yes you guessed it right, you need an AVR programmer. It’s pretty easy to buy one fully built and programmed.

Some of the features include:• Allows you to read or write the microcontroller EEPROM, firmware, fuse bits and lock bits• Support for Windows, Mac OS X and Linux (will work on Windows 8.1)• 5 KB/sec maximum write speed• Software controlled SCK option to support targets with low clock speed (< 1.5MHz)• 10 pin ISP interface (conforms to standard ISP 10-pin pinout)• The latest Window Drivers are fully signed, so you can use them on Windows Vista and

above without any issues. The driver will work on both 32 and 64 bit platforms. On Linux And Mac OS X no kernel driver is required, just use AVRdude and specify the correct port.

• The programmer will work with a wide variety of Atmel AVR microcontrollers including the Atmega8a and Atmega168a. A full list is available on the specifications tab.

USBASP used: First hand look

DSP PROCESSOR

A digital signal processor (DSP) is a specialized microprocessor with its architecture optimized for the operational needs of digital signal processingThe goal of DSPs is usually to measure, filter and/or compress continuous real-world analog signals.A DSP Processor can process data in real time, making it ideal for applications that cannot tolerate delays.A DSP Processor takes a digital signal and processes it to improve the signal into clearer sound, sharper image or faster data.

We have used an EnTuino DSP Processor for the simple purpose of performing simultaneous and continuous conversion of mp3 formatted audio files to give us a much clearer output.

SPI INTERFACE

SPI is a synchronous serial data link that operates in full duplex mode. It is primarily used for short distance, single master communication. As we already know, the master initiates the data frame and multiple slave devices are allowed with specific select lines. We have used an SPI interface to basically link our AtMega 162 Microcontroller with the DSP Processor.

What does LCD mean?A liquid-crystal display (LCD) is a flat panel display or video display that uses the

light modulating properties of liquid crystals. Liquid crystals do not emit light directly.

LCDs are available to display arbitrary images (as in a general-purpose computer display) or fixed images which can be displayed or hidden, such as preset words,

digits, and 7-segment displays as in a digital clock.

In our project, we have used a GLCD5110 LCD display. It has the following features:- 84 X 48 pixels resolution- Built-in PCD8544 controller with SPI interface bus.- Built-in the backlight blue LED controlled by software- Supply voltage range is +3 to +3.3V. Maximum current is 10mA (with backlight LED)- Display the standard size 5x7 pixel character up to 14 characters 6 lines and mono-tone graphic image.- Size is 4.5 x 4.5 cm.- Easy to connection- Interface with any popular microcontroller.

GLCD5110 LCD

To conclude, we have designed an MP3 player using an AtMega 162 Microcontroller to control our LCD and Keypad, a DSP Processor to convert the MP3 format to rich quality audio files and to operate in real time without any apparent delay. We successfully interfaced and programmed the devices with the help of the code provided to us.For interfacing, we used connecting wires and for implementing the C program, we used the USBASP.

THANK YOU!