DIY MP3 Player

[Canada EH]

I was thinking about my little ipod with its 16GB of memory.

Then I saw some 1st gen ipods with 8GB or 16GB for real cheap ~$10.

But I want something in the 64GB range, which is very pricey.

I figured I needed to search the interweb and I found a few DIY but they looked complicated.

I stumbled across Adruino Spark Fun Shield - https://www.sparkfun.com/products/12660

And was thinking it would be cool to have a compact MP3 player that may be able to play radio with the right add ons.

Now though cell phones have capabilities of 256GB of memory via SD card. I could just buy me a phone like that, since my contract is almost up. But I'd prefer a separate device. Less drops, and saves my cell phone battery power.

 

I bought an expensive kit a year ago, from Adafruit, I wanted to do a GPS for my expensive e-bicycle, but was in way over my head and returned it.

 

 

Are there any Adruino kits that use 64GB or higher SD cards that has a AM/FM digital tuner?

 

 

 

 

[Guest]

I bought a while ago a SIM card, with 15 euro's on it. (after registering the number) Got a free Nokia 108 with the SIM card. It plays "good enough" FM radio, and it also plays (stereo) mp3 files, if I put in my 2 gb micro SD card.

 

I use this thing to take random pictures in LOW quality, use it as my alarm clock (hooked up to some cheap speakers with good sound quality), and I use it as a bathroom radio (with 5.1 old creative speakers, all hooked up to 1 3.5 mm jack)

 

Don't think it will get any cheaper then that.

[Canada EH]

I am looking for cheap, used cell phones that have a SD card and FM radio. I never listen to AM, except I do like certain talk radio on the AM dial.

I keep telling myself and try to pump myself up to do an Adruino, but I pussy out of it. Hopefully these older phones can take 64GB, I'd be happy.

[mariushm]

Cheap music players are basically system-on-chip devices, with dual DAC (digital to analogue converters), some sram/ram , and basically they run a tiny linux operating system or some other embedded os.

Arduino is using a 8 bit microcontroller , with low frequencies and not enough ram and memory for programs to even support file formats ... you'd basically use it as glue between fm tuner chip, audio decoder chip, audio amplifier chip so it's not worth it.

In addition, something that would be fast and easy to read (and use little program code) using a microcontroller would be FAT32 ... and Windows limits you to maximum 32 GB with FAT32 partitions. Maybe you could create two partitions on the SD card but it would be ugly.

 

A PIC32 would be powerful enough to read data from SD card, may use DMA to transfer it through the internals if needed, some versions have DACs integrated to decode the digital to analogue which then can be passed to a class D amplifier on the circuit board...

PIC32s can run as high as 80-100 Mhz (much later edit: some new PIC32MZ can go as high as 250 Mhz), they're 32 bit ... there's existing free libraries to decode MP3 with them such as this one or there's commercial libraries which can also decode AAC and WMA from Microchip like this one and there's also FLAC decoders for them, see here  (this guy passes the decoded digital data to a chip that's 2 DAC + headphone amplifier in one)  : http://www.microchip.com/forums/m399956.aspx

 

pics and sd cards and fat32 etc : http://www.microchip.com/SWLibraryWeb/product.aspx?product=Memory Disk Drive File System

 or http://www.studentcompanion.co.za/interfacing-sd-card-fat32-system-with-pic-microcontroller-mikroc/

 or http://hades.mech.northwestern.edu/index.php/PIC32MX:_Interfacing_to_a_Secure_Digital_(SD)_Flash_Card

 

So if you're willing to learn some basic C and buy a programmer and settle with just a 32 GB card (or maybe 2 cards and switch between them in the interface of your music player), you could build such a project with about 10$ (4-6$ for a pic32 and maybe 2$ for an amplifier / 2dac) .. of course, the programmer for PIC chips is about $30-$40 but it's one time investment, worth the money.

Something like this  PIC32MZ0512EFE064[/urll] is powerful enough to handle everything but if you want you can go to town and spend 12$ on chip with 2 MB of program space (compared to the linked one with only 512KB) and 256-512 KB of ram (vs 128KB the linked one has).

 

For radio, there are FM tuner chips like this one for example : http://www.digikey.com/product-detail/en/silicon-labs/SI4705-D60-GMR/SI4705-D60-GMR-ND/4069345

They can be controlled through SPI and can send audio data digitally back to a microcontroller (which will pass on to audio amp+dac chip or convert to analogue in controller if it has dacs or send to separate DAC chips and then it goes to audio amplifier for headphones), or they (not all chips, this one does) can output analogue sound through their own built in DACs ... you would connect the output to a headphone amplifier.

There are cheaper am/fm tuner chips if you buy in small quantity, like TDA7703 but you'd pick one which has the best documentation for one off projects, not necessarily the cheapest or the one with lowest pin count. See datasheet of this TDA7703 and look at page 29 for an example of circuit that would support both am and fm : https://media.digikey.com/pdf/Data Sheets/ST Microelectronics PDFS/TDA7703_Rev1.pdf

[Canada EH]

1 hour ago, mariushm said:

So if you're willing to learn some basic C

No

 

1 hour ago, mariushm said:

you could build such a project with about 10$

Maybe willing to learn, maybe.

 

 

[mariushm]

The IDE of your Arduino uses some made up language that is very similar to C and before uploading the code to your ARduino, it converts the code you wrote (the sketches) to C and then the compiler converts that to binary code and that's uploaded to Arduino..so in essence if you wrote sketches in Arduino, you already used a light version of C.

 

PICs are very similar to Atmel chips used in Arduinos, the same concepts apply to PIC chips as well. It wouldn't be that much of a difference to download some example programs or read some tutorials for PIC16 or PIC32 and browse the code and see what they're doing. With basic C knowledge you could easily do lots of things.

 

Anyway, it is an investment, you do need the programmer which is kind of expensive but it's a one time purchase.

 

[fjdhdhcyfhf]

9 hours ago, Canada EH said:

No

If you dont want to learn C; buy a consumer device. Your local telco should be able to hook you up with a dirt cheap android. I have a cheap NZD$34 vodafone locked android phone that can take SD card and would be what you are looking for; has a FM radio, is the size of a credit card & has internet radio. Its locked to Vodafones network on a no contract prepay plan but it doesn't cost me anything because I dont use it as a cell phone