Hi everybody, i'm student on the UPV of Valencia and i'm trying to port the Andreas Schwarz MP3 Player to a ST M3 Cortex. I have a problem when i compile the code with keil: Error[Li005]: no definition for "xmp3_UnpackFrameHeader" [referenced from C:\IAR Systems\Embedded Workbench 5.4\arm\examples\ST\STM32F10x\ IAR-STM32F103ZE-SK\ARMP3\Flash Debug\Obj\mp3dec.o] Can someone give me help and tell me where can be the problem? Thank's everybody. Excuse me for my english, it's very bad.