I'm developing a application with PN532 card reader through SPI. I'm using libfreefare library to communicate with Mifare DESfire EV1 mainly. My problem is in the reading speed I'm getting. I've to read about 11 files on the card and I'm getting about 700ms for read them. For my application, this time is very high, and I'm trying to reduce it. I've thought about changing the speed of the spi and increasing the speed when negotiating the communication with the desfire, but while I try, does anyone have any ideas that I can apply to improve these reading times?


  • 1
    The SPI speed is unlikely to be the bottleneck. You need to profile the library calls (i.e. timestamp) to find which ones are taking an excessive amount of time.
    – joan
    May 10 '18 at 8:08
  • @joan thanks for your comment. As I said before, it takes a lot of time to read the files. According to my checks the reading rate is 12 kbps but it should be close to 424kbps. I 've changed spi speed with the same results as you expected
    – crossmax
    May 18 '18 at 6:32

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