lpcware

Inverted SD_CLK on LPC4337

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by jgorsk on Fri Oct 03 00:32:12 MST 2014
Is there any reason why SD_CLK line on the LPC4337 in LQFP144 would be inverted? When a command is sent to SD card,
active edge of SD_CLK is the falling edge. Therefore the card is not replying. When I delay SD_CMD slightly with a simple RC
circuit, the card actually starts replying.

This happens during the initialization of the card when the clock frequency is 400kHz. I'm using CLK0 pin for SD_CLK.

I'm running this on my own board with no SDRAM.

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