MC2GH256NMCA-2SA00 SAMSUNG [Samsung semiconductor], MC2GH256NMCA-2SA00 Datasheet - Page 40

• Manufacturer Part Number: MC2GH256NMCA-2SA00
• Description: SAMSUNG MultiMediaCard
• Manufacturer: SAMSUNG [Samsung semiconductor]

By omitting the voltage range in the command (by setting the argument of CMD1 to 0), the host can query the card and
determine the voltage type of the card. This bus query should be used if the host is able to select a common voltage
range, or if a notification to the application of a non usable card in the bus is desired. Afterwards, the host must choose a
voltage for operation, and reissue CMD1 with this condition, sending incompatible cards into the Inactive State.
The busy bit in the CMD1 response can be used by a card to tell the host that it is still working on its power-up/reset pro-
cedure (e.g. downloading the register information from memory field) and is not ready yet for communication. In this case
the host must repeat CMD1 until the busy bit is cleared.
During the initialization procedure, the host is not allowed to change the operating voltage range. Such changes shall be
ignored by the card. If there is a real change in the operating conditions, the host must reset the card (using CMD0) and
restart the initialization procedure. However, for accessing cards already in Inactive State, a hard reset must be done by
switching the power supply off and back on.
The command GO_INACTIVE_STATE (CMD15) can be used to send an addressed card into the Inactive State. This com-
mand is used when the host explicitly wants to deactivate a card (e.g. host is changing V
be not supported by this card).
Revision 0.3
Interrupt mode
Wait-IRQ State
(irq)
card is busy or
host omitted voltage range
Figure 6-1 : MultiMediaCard State Diagram (Card Identification Mode)
Any start bit detected on the bus
card looses bus
CMD40
data-transfer mode
Power on
Ready State
Stand-by State
Identification
State (ident)
Idle State
CMD1
CMD2
CMD3
(ready)
(stby)
(idle)
40
cards with non compatible voltage range
card wins bus
card-identification mode
CMD0
data-transfer mode
State (ina)
Inactive
DD
from all states except (ina)
into a range which is known to
MultiMediaCard
from all states in
data-transfer-mode
CMD15
Sep.22.2005
TM