SD\MMC issue

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Aug 16, 2016 by zzzmqp
Content originally posted in LPCWare by mirfan on Mon Sep 24 05:49:52 MST 2012

I received a Hitex LPC4350 Eval board. I am currently porting SD\MMC driver using my own state machine so I am not using the driver from the LPC driver library. The issue i am having right now is that the command phase of SD\MMC card initialization completes without a hitch, but as soon as I make a data transaction over DMA, it generates a Data CRC error. Even if I do get a DMA transaction, the received data is invalid. One thing that I doubt to be the culprit is the SD clock source multiplexing. The SD clock is multiplexed with EMC controller clocks for external SDRAM. So, can SD\MMC be used along with external SDRAM? (I am currently running my image from external SDRAM)