SDI Technologies SDIO Card manual To abort transfers to/from memory

©Copyright 2000-2007 SD Card Association

SDIO Simplified Specification Version 2.00

Field	Type			Description
SDx	R/O		SD Format Version number. These 4 bits contain the version of the SD Physical
			Specification that this card supports. The codes for the SD Physical Specification are
			as follows:
			Value	SD Physical Specification
			0x00	SD Physical Specification Version 1.01 (March 2000)
			0x01	SD Physical Specification Version 1.10 (October 2004)
			0x02	SD Physical Specification Version 2.00 (May 2006)
			0x03-0x0F	Reserved for Future Use
IOEx	R/W	Enable Function - If this bit is reset to 0, the function is disabled. If this bit is set to 1,
			the function is enabled to start its initialization. The completion of initialization is
			indicated in IORx. On power up or after a reset, the card shall reset this bit to 0. The
			host can also use IOEx as a per function reset for error recovery. The host sequence
			for a per function reset is to reset IOEx to 0, wait until IORx becomes 0 and then set
			IOEx to 1 again. If the error is not recovered by this sequence, SDIO reset should be
			used noting that the operation of all functions will be aborted. See section 11 for
			relation to Master Power Control and Power Select.
IORx	R/O	I/O Function Ready- If this bit is reset to 0, the function is not ready to operate. This
			may be caused by the function being disabled or not ready due to internal causes
			such as a built-in self-test in progress. If this bit is set to 1, the function is ready to
			operate. The functions shall set this bit to 1 within the timeout value defined in the
			TPLFE_ENABLE_TIMEOUT_VAL tuple. On power up or after a reset, this bit shall
			be set to 0. For any function that is not implemented on an SDIO card, this bit shall
			always be 0.
IENx	R/W	Interrupt Enable for function x. If this bit is cleared to 0, any interrupt from this function
			shall not be sent to the host. If this bit is set to 1, then this function’s interrupt shall be
			sent to the host if the master Interrupt Enable (bit 0) is also set to 1.
IENM	R/W	Interrupt Enable Master. If this bit is cleared to 0, no interrupts from this card shall be
			sent to the host. If this bit is set to 1, then any function’s interrupt shall be sent to the
			host.
INTx	R/O		Interrupt Pending for function x. If this bit is cleared to 0, this indicates that no
			interrupts are pending from this function. If this bit is set to 1, then this function has
			interrupt pending. Note that if the IENx or IENM bits are not set, the host cannot
			receive this pending interrupt.
ASx	W/O		Abort Select In order to abort an I/O read or write and free the SD bus, the function
			that is currently transferring data must be addressed. These 3 bits define which
			function’s transfer to stop. For example, the abort the transfer to function number 3,
			the value of 0x03 would be written to these bits using CMD52 only. If the abort is
			addressed to a suspended function, it does not affect current data transaction. Note
			that this is an abort, not a reset. The addressed function shall return to the CMD state
			and data transfer pending to that function shall be halted. This abort procedure does
			not work for SPI write operations. To abort an SPI write data transfer use the
			STOP_TRAN token as defined in section 7.3.3 of the SD Physical Specification. This
			form of abort applies only to the functions of an SDIO card. For the memory of a
			combo card, the abort methods defined in the SD Physical Specification shall be used
			to abort transfers to/from memory
RES	W/O	I/O CARD RESET: Setting the RES to 1 shall cause all I/O functions in an SDIO or
			Combo card to perform a soft reset. Setting the RES to 1 does not affect the current
			card protocol selection(SD vs. SPI mode) and CD Disable. Setting of the RES bit
			shall only be performed using CMD52. When RES=1, the values of AS2-0 are
			don’t-cares. The RES bit is auto cleared, so there is no need to rewrite a value of 0.
			This bit is write-only, any read returns an undetermined value. Memory in a combo
			card is not affected.

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