James, I've also been concerned about the SD data rate for a data-logging=20 device that I'm slowly working on, as I'm expecting to capture data just=20 a bit above the max rate of the SD card. But I really want the data to=20 be on a removable data card, so I'm considering circular-buffering the=20 data to a RAM chip, and streaming that out to the SD card at the lower=20 rate. With the 4GB SD limit, I won't need 4GB of RAM, but I've ballpark=20 calculated I'd need just under 1 GB of RAM. Just need to figure out the=20 lowest cost option for the RAM. The values in RAM would be raw, then in=20 FAT32 format only when it's on the SD. I'll also consider compressing the data as it may help eliminate the=20 need for the buffer RAM.. As for the FAT32 4GB limit, I'm pretty sure the next level (exFAT IIRC)=20 is proprietary/closed/expensive, so perhaps format the SD card into=20 multiple 4GB partitions with the partitions labelled so you can get them=20 back in order? This would depend on how you plan to retrieve them. Cheers, -Neil. On 5/12/2016 4:31 AM, James Burkart wrote: > I aspire to make a small audio recorder. I need to decide how and on what > it will record on, and how I will retrieve the files. > > I was originally considering having it record to microSD. Initial obstacl= es > I found were speed limitations from using SPI, and the FAT32 drivers I wa= s > looking into will only access up to 4GB. > > FAT Driver I am reading up on. > *http://www.embedded-code.com/source-code/memory/secure-digital-mmc-memor= y-cards/secure-digital-mmc-memory-card-fat16-fat32-driver > * > > Alternatively I was considering having the recorder write to flash memory > and then retrieving the files via USB interface. I know next to nothing > about attempting this method. Immediate obstacles for me would be figurin= g > out the whole USB thing, and finding/writing FAT32 drivers for use with t= he > flash memory (or do I?). > > USB stuff I have found. > *http://www.signal11.us/oss/m-stack * > > I would appreciate any thoughts or input, suggestions, sources to read, > what to consider, etc... > What questions should I be asking myself? > > Note: I would like to be able to record stereo 48kHz/24-bit but I will > settle on mono 44.1kHz/16-bit. > > -- > James Burkart --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .