NAND08GAH0A NUMONYX [Numonyx B.V], NAND08GAH0A Datasheet - Page 85

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

NAND08GAH0A, NAND16GAH0D
10.4
10.4.1
SPI bus protocol
While the MultiMediaCard channel is based on command and data bit streams which are
initiated by a start bit and terminated by a stop bit, the SPI channel is byte oriented. Every
command or data block consists of 8-bit bytes and is byte aligned to the CS signal (i.e. the
length is a multiple of 8 clock cycles).
Like in the MultiMediaCard protocol, the SPI messages consist of command, response and
data-block tokens (see
by the host (master). The host starts every bus transaction by asserting the CS signal Low.
The response behavior in the SPI mode differs from that in the MultiMediaCard mode in the
three following aspects:
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Only Single and Multiple Block Read/Write operations are supported in SPI mode
(sequential mode is not supported).
In addition to the command response, a special data response token is returned for every
data block sent to the device during write operations. A data block may be as big as one
device write block and as small as a single byte. Partial block read/write operations are
enabled by device options specified in the CSD Register.
Mode selection
The MultiMediaCard wakes up in the MultiMediaCard mode. It enters the SPI mode if the
CS signal is asserted (negative) during the reception of the reset command (CMD0). The
SPI mode can also be selected from other states than the Idle state (the state the device
enters after power-up). Every time the device receives CMD0, even while the device is in the
Inactive state, the CS signal is sampled.
If the device recognizes that the MultiMediaCard mode is required (CS signal is High), it
does not respond to the command and remains in the MultiMediaCard mode. If the SPI
mode is required (CS signal is Low), the device switches to the SPI mode and responds with
the SPI mode R1 response.
The only way to return to the MultiMediaCard mode is by a power-down cycle (turn the
power off an on). In SPI mode, the MultiMediaCard protocol state machine is not observed.
All the MultiMediaCard commands supported in the SPI mode are always available.
The selected device always responds to the command
Additional (8, 16 & 40 bit) response structures are used
When the device encounters a data retrieval problem, it responds with an error
response (which replaces the expected data block) instead of a timeout in the
MultiMediaCard mode.
Section
4). All communication between host and device is controlled
Serial peripheral interface (SPI) mode
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