SMS02GDFB5E NUMONYX, SMS02GDFB5E Datasheet - Page 21

• Manufacturer Part Number: SMS02GDFB5E
• Description: MICROSD CARD SMS 2GB FLASH MEM
• Manufacturer: NUMONYX

Specifications of SMS02GDFB5E

• Memory Size: 2GB
• Memory Type: SD (Secure Digital)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

SMSxxxDF
CMD7 is used to select one card and switch it to the transfer state. Only one card can be in
transfer state at a given time. If a previously selected card is still in transfer state when the
host uses CMD7 to switch another card to the transfer state, then the connection between
the previously selected card and the host is released and the card reverts to the standby
state.
When CMD7 is issued with the reserved relative card address ‘0000h’, all cards revert to the
standby state. This function may be used before identifying new cards, to avoid resetting
already registered cards. When in standby state the cards that already have an RCA do not
respond to identification commands (CMD41, CMD2, CMD3).
Note that a card is deselected when it receives a CMD7 with an RCA that does not match.
Card deselection is automatic if another card in a system is selected and the cards share
the same CMD lines.
So, in an SD memory card system, the host may either have a common CMD line for all SD
memory cards (in which case card deselection is automatic just like in a MultiMediaCard
system) or the host may have separate CMD lines, in which case it must be aware of the
necessity of deselecting cards.
All data communications in the data transfer mode are point-to point between the host and
the selected card (using addressed commands). All addressed commands are
acknowledged by a response on the CMD line.
The relationships between the various states in the data transfer mode are summarized
below (see
If all write buffers are full, the DAT0 line will remain Low (busy) as long as the card is in the
programming state (see
All Data Read commands (CMD17, CMD18, CMD30, CMD56, ACMD51) can be
aborted at any time using the Stop command (CMD12). The data transfer will terminate
and the card will return to the transfer state
All Data Write commands (CMD24,CMD25, CMD26, CMD27, CMD42, CMD56) can be
aborted at any time using the Stop command (CMD12). The write commands must be
stopped prior to deselecting the card using CMD7
As soon as the data transfer has completed, the card switches from the data write state
to either the programming state (if the transfer was successful) or the transfer state (if
the transfer failed)
If a block write operation is stopped and the block length and CRC of the last block are
valid, the data will be programmed
The card can provide buffering during block write. This means that the data to be
programmed to the next block can be sent to the card while the previous block is being
programmed.
There is no buffering option for write CSD, write CID, write protection and erase. This
means that while the card is busy with any one of these commands, no other Data
Figure
12):
Figure
12).
Secure digital memory card interface
21/60