Does anyone know where can I find documentation on interfacing with the MOD-MP3 board?
Is the specification for the UEXT connector available somewhere?
Is there code resident on the board as shipped that will allow stand-alone operation?
I just bought two of the modules and I thought they would come with some documentation. The Olimex website provides a schematic (but no info on the operation of the UEXT connector) and some sample LPC-P2148 demo code (but this consists of about 100 separate unexplained files for a processor I’ve never programmed before).
Most all of the information you requested is available here: http://www.sparkfun.com/commerce/produc … ts_id=7832 . The UEXT connector is diagrammed there. The software that is linked to on this page is for an LPC-P2148 which you would have to buy separately, as the MOD-MP3 board has no onboard microcontroller. With that said, you don’t have to worry about putting any code onto your MOD-MP3 board, only a microcontroller board that you would buy yourself that would control the MOD-MP3.
The device can act as a stand-alone MP3 player by putting a music on an SD card and inserting it into the board. I’m not sure about configuration switches or whatever it takes to get it to work in this way, however, as I don’t own the board. There appear to be a bunch of jumpers on that board, so take a look at the schematic or flyer to see if you can figure out what each setting does. If all else fails, just try stuff. :lol:
True the MOD-MP3 board has no onboard microcontroller but it does have an onboard EEPROM and it boots from this in stand-alone mode. Another post on this forum lead me to believe I might have to program the EEPROM myself before things would work but that is not true.
You’re right, this EPROM comes preprogrammed for basic operation and this operation is essentially the same as that described for VLSI’s own development board which is much better documented: http://www.vlsi.fi/player_vs10xx_proto/player.shtml
Here’s the quick start guide:
add power (AA battery)
make sure the EXT/BAT jumper is set to BAT
make sure the DREQ_E jumper is in place for stand-alone operation (I think this needs to be removed for control over UEXT)
insert headphones
use the switch as follows:
move left briefly - next song
move right briefly - last song
press in briefly - play/pause
move left and hold - volume up
move right and hold - volume down
press in and hold - if playing this will toggle loudness, if paused it will toggle random play
Well, yes. I loaded the file “player1002sci.c” into PonyProg, and transferred it via PonyProg into the MOD-MP3’s onboard eeprom. PonyProg does a verify of the transfer and confirmed it.
As to confirm the program is running, I have no way really to check this… Some clue I have to know something’s working is that sound will play under certain reset circumstances when I insert the SD card.
P.O.:
Well, yes. I loaded the file “player1002sci.c” into PonyProg, and transferred it via PonyProg into the MOD-MP3’s onboard eeprom. PonyProg does a verify of the transfer and confirmed it.
P.O.
I think that he was asking if you really loaded the “player1002sci.c” TEXT file, which of course, is not actually an executable file. It is the C source code in text format. You would actually need to download the “player1002sci.bin” file, which is the executable binary file.
I am sort just guessing at what your hardware actually is but if I guessed right then I think that this document might be helpful???
Oh, I have read this document many times! The biggest problem I have is in the communication between the MOD-MP3 and the Basic Stamp 1: sending and receiving the data the right way, and guessing which lines are really necessary and which ones are not, and the logic levels between the two…
P.O.:
Oh, I have read this document many times! The biggest problem I have is in the communication between the MOD-MP3 and the Basic Stamp 1: sending and receiving the data the right way, and guessing which lines are really necessary and which ones are not, and the logic levels between the two…
P.O.
I am going to try this with a 5V PICDEM 2 PLUS board and will let you know if I can get it to work. I am going to convert 5v to 3v before attempting to talk to the MOD-MP3. Did you every try the voltage conversion?
I have tried with a Basic Stamp II and resistors between the MOD-MP3 and the Stamp, and I have tried with a directly connected Basic Stamp I operating at 3.3V, with no success.