Just bought a used Lowrance LMS 522 to use with me Xi5 trolling motor transducer. The manual talks about a MMC card, is that the same as an SD card, the slots are the same? I tried converting Garmin waypoints with GPS visualizer, loading them on an SD card, but the 522 doesn't seem to recognize the card. It's a 4g card, is that a problem? Thanks, Ron