自制MP3播放器

文章摘要：简述：此款名为yampp-7型MP3播放器，用了一片Nokia3310手机的LCD显示屏来显示操作，使用一片FT8U245USB芯片！能使用多种小型Flash卡和多媒体卡作为歌曲文件存储器！yampp7 is a new portable MP3 player that uses ComPACt Flash or MultiMedia cards for storage of songs. You'll get about 1 minute of playing time per MB on the memory card, if your songs are 128 kbps.The

自制MP3播放器,标签：电子小制作,http://www.88dzw.com

简述：此款名为yampp-7型MP3播放器，用了一片Nokia3310手机的LCD显示屏来显示操作，使用一片FT8U245USB芯片！能使用多种小型Flash卡和多媒体卡作为歌曲文件存储器！

yampp7 is a new portable MP3 player that uses ComPACt Flash or MultiMedia cards for storage of songs. You'll get about 1 minute of playing time per MB on the memory card, if your songs are 128 kbps.

The player is pretty small and the PCB has been designed to fit into a Teko "Soap" box.

It features a 84*48 pixel graphICal LCD display, similar to the displays used on Nokia 3310 cell phones.

It's designed to operate from rechargable battery cells, either from a single 3.6V Li-Ion cell (recommended), or from 3*1.2V Ni-Mh cells. With a 600 mA Li-Ion cell, the playing time is about 12 hours, but you CAN find Li-Ion cells up to 1200 mAh that will fit in the player, extending the playing time to about 24 hours

It's intended to be used with replacement Li-Ion cells for Mobile Phones, making it easy (and relatively cheap) to find a suitable cell. (I use mine with a cell for a Motorola V3688 Phone).

It also features a USB interface for fast downloading of songs to the memory card, and for firmware updates

The player uses a special filesystem calLED YADL (Yampp Advanced Disk Layout), which maximizes the capacoty of the memory card.

It is playlist based and give the player a powerful but easy to use user interface

Processor

The central part of the yampp-7 player is the Atmel mega161 CPU. It's like a big-brother to the classic 8515 CPU that was used on the original yampp-3.

It has 16 kB Flash and 1024 bytes internal SRAM, both double as much as on the 8515.

It also features a bootloader option. This is been used in yampp-7, where it is now possible to download new firmware over the USB link

USB

The USB link is controlled by a FT8U245BM Chip from FTDI. This is a VERY easy to use USB chip, which basically looks like a simple 8-bit buffer (hence the name). There's no need for implementing any specific USB code in the player, to communicate over the USB link, you just read and write data directly to the chip.

Two status PINs inDICate if there's any data in the receive buffer, and if the transmitter queue is empty.

The USB chip is memorymapped and oCCupies a single address in the CPU address space.

Some discrete circuitry is added to the USB chip to enable it to startup in the correct mode, and to handle the power on reset and SOFt-Connect feature.

Li-Ion charger

A Maxim MAX1811 chip is added for handling the charging of the Li-Ion cell.(Ni-Mh cells can also be used in the player, in this case, the MAX1811 is replaced by a diode and a resistor).

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