diff --git a/tornado/fw/mmc-hw.c b/tornado/fw/mmc-hw.c
index 6682423..c4c0a4f 100644
--- a/tornado/fw/mmc-hw.c
+++ b/tornado/fw/mmc-hw.c
@@ -104,10 +104,14 @@ void mmc_activate(void)
 	SET(MMC_nCS);
 	CLR(MMC_CLK);
 	OUT(MMC_nCS);
+	SET(MMC_MOSI);
+	SET(MMC_CLK);	/* for pre-charging */
 	OUT(MMC_MOSI);
 	OUT(MMC_CLK);
 	IN(MMC_MISO);
 
+	_delay_ms(100);	/* allow card to pre-charge, to limit inrush current */
+
 	CLR(CARD_nPWR);
 
 	_delay_ms(10);