SDI Technologies SDIO Card manual Card initialization flow in SPI mode Sdio aware host

©Copyright 2000-2007 SD Card Association

SDIO Simplified Specification Version 2.00

			C				D
				Skip memory initialize or MEM=1
		Test MEM Flag
			Execute memory initialize & MEM=0
			CMD58	Get memory OCR
	Illegal Command	Check Response			OCR invalid
			OCR valid
		Set New Voltage (if needed)
			High Capacity Support Host: HCS=1
		ACMD41 Arg=HCS, WV
	IDLE=1	Check Response			1sec Timeout
			IDLE=0
			MEM=1	Memory Initialized
	Illegal Command		CMD58	If F8=1, CMD58 is required
				to get CCS. If F8=0, CSS=0.
			Test Flags			IO=0, MEM=0
	IO=0, MEM=1				MEM=1
			MEM=0
Not SD	Test CCS		IO Only		Test CCS		Unusable card
			Card
Card	CCS=0	CCS=1		CCS=0		CCS=1
	Standard	High		Standard		High
	Capacity	Capacity		Capacity		Capacity
	Memory	Memory		Combo		Combo
	Only Card	Only Card		Card		Card

Variables
NF:	Number of I/O Functions (CMD5 Response)
MP:	Memory Present Flag (CMD5 Response)
IORDY:	I/O Power-up Status (C bit in the CMD5 response)
MRDY:	Memory Power-up Status (OCR Bit31)
HCS:	Host Capacity Support (ACMD41 Argument)

CCS:	Card Capacity Status (ACMD41 Response)
Flags
IO:	I/O Functions Initialized Flag
MEM:	Memory Initialized Flag
F8:	CMD8 Flag

Figure 3-3 Card initialization flow in SPI mode (SDIO aware host)

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