I've been working on an SD card music player for a personal project and have been looking everywhere for an answer to this question. I simplified the Synthesizer example included with the board so that now all I need to do is get the audio data from the SD card.
For some reason, the SD Card music player demo included with the board won't work on my system. Therefore, I'm trying to find a way to read the audio data without needing NIOS II. Any advice? Maybe a resource to see how to implement it?
Probably depends on the SD card format. For simply reading blocks starting at a known block number, you can probably write a state machine to do it.
But to read from a FAT file system ... forget it, you'll be better off with a CPU (NIOS etc)
If u are trying to use demo codes. try to format the sdcard in FAT16, which should be less than 2GB. otherwise it wont work
Else, Go for SD Card protocol, declare PIO's according to the requirement and use standard C library to access the data.
http://www.roland-riegel.de/sd-reader/ change according to the PIO access API's for NIOS II BSP
