NAND08GAH0A NUMONYX [Numonyx B.V], NAND08GAH0A Datasheet - Page 42

• Manufacturer Part Number: NAND08GAH0A
• Manufacturer: NUMONYX [Numonyx B.V]

High speed MultiMediaCard operation
5.6
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To use one of the application specific ACMD commands, the host must follow the steps
described below:
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GEN_CMD command (CMD56)
Bus operation during a GEN_CMD command is identical as Single Block Read or Write
commands (CMD24 or CMD17). The only difference is that the argument indicates the
direction of the data transfer (rather than the address) and the data block is not a memory
payload data but has a vendor specific format and meaning.
The card must be selected (Transfer state) before the host sends a CMD56 command. The
data block size is specified in the BLOCK_LEN defined with CMD16. The response to
CMD56 will be of R1 type.
Clock control
The device bus clock signal can be used by the host to set the device to energy saving mode
or to control the data flow on the bus. The host is allowed to lower the clock frequency or
shut it down.
There are a few restrictions the host must follow:
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The host is allowed to shut down the clock of a busy device. The device will complete the
programming operation regardless of the host clock. However, the host must provide a clock
edge for the device to turn off its busy flag. Without a clock edge the MultiMediaCard (unless
previously disconnected by a deselect command CMD7) will force the DAT line Low,
permanently.
Send the APP_CMD command. The device will respond with APP_CMD bit (new
status bit) of the response set to ‘1’ to signal to the host that ACMD is now expected.
Send the required ACMD command. The device will respond with APP_CMD bit set,
indicating that the accepted command was interpreted as an ACMD command.
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The bus frequency can be changed at any time, under the restrictions of maximum data
transfer frequency and the identification frequency
The clock must be running for the device to output data or response tokens
After the last bus transaction, the host is required to provide 8 clock cycles for the
device to complete before shutting down the clock.
If a non-ACMD command is sent, then the device will handle it as a normal
command, and the APP_CMD bit in the Card status will remain set to ‘0’.
If a non valid command is sent (neither ACMD nor CMD) then the device will
handle it as a standard MultiMediaCard illegal command.
NAND08GAH0A, NAND16GAH0D