DiY: most tiny MP3 player with ATmega8 VS1011a and Nokia6100 Display

This is a complete mobile MP3 player and first mp3-player with ATmega8 and Nokia 6100 color display.

An demo firmware and gerber file for board will be available soon.

This player has capability to play wav and mp3 files and view BMP files on 8 or 24 bits/pixel from a MicroSD card with maximum capacity 2GB, the format of the SD is FAT32 with clusters from 512 Bytes to 32768Bytes, the filesystem has no limits in number of directories and files.
For future i want to adapting the SD driver for SDHC because the filesystem is designed to use all capacity of fat32 ( 2TB in 512Bytes/sector)

List of features:
Play Wav and MP3 Files because the VS1011a only this files is capable to decode( but for future in this project i want to include the VS1053 chip to play more file formats.
View Bitmap files on 8Bit and 24 bit/pixel

This project is in asm language and my 100% own libraries









For the moment the project has 5172Bytes of Flash , 663Bytes of Ram and 0Bytes of EEprom

I work to another MP3 player:
New MP3 Player Link

Real schematik to interface a SD/MMC card to atmega microcontrollers

Because many sites operate a scheme to connect an SD/MMC card to a ATmega microcontroller that is non functional, I mean scheme with dividing resistive to the ground, I decided to post an overall scheme real functional and will post and parameters operation of a card at different voltages, everything after more probe:

We know that most cards SD/MMC operates in a voltage between 2.7 and 3.6 V, I will recommend one to use the minimum operating voltage.
However such a card works at 5V supply voltage without any risk of failure, but a voltage across the card manufacturer's specifications will work only read data and read CID etc. Write delete functions will not work

SD/MMC card and ATmega at diferent voltages:





SD/MMC card and ATmega at same voltages: