AT88SC0404CA-Y6H-T Atmel, AT88SC0404CA-Y6H-T Datasheet - Page 32

• Manufacturer Part Number: AT88SC0404CA-Y6H-T
• Description: IC EEPROM 4KBIT 4MHZ 8MAP
• Manufacturer: Atmel
• Series: CryptoMemory®r

Specifications of AT88SC0404CA-Y6H-T

• Format - Memory: EEPROMs - Serial
• Memory Type: EEPROM
• Memory Size: 4K (512 x 8)
• Speed: 4MHz
• Interface: I²C, 2-Wire Serial
• Voltage - Supply: 2.7 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-UDFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8.5.
8.6.
8.7.
8.7.1. Functional
8664C–CRYPT–01/10
Device Addressing
The first nibble of the command byte corresponds to the device address. All Atmel
respond to the device address $B. A specific device may be set to respond to another value ($0 to $F) in addition to $B
by setting this value in the second nibble of the Device Configuration Register (DCR) in the configuration memory. The
DCR is set to $FF at the Atmel factory and thus will respond to device address $B and $F unless the DCR is modified.
For a device to respond only to $B the DCR should be set to $B also.
TWI Command Descriptions
In the following section operations are described in two parts: the instruction is described first from a functional point of
view (parameters and data exchanged), after which they are detailed for the synchronous two-wire protocol. In these
diagrams, values are shown in binary format with bits to the left transmitted first, i.e. bytes are transmitted most
significant bit first.
Write User Zone: $B0
Figure 15. Write User Zone Command Functional Description
The Write User Zone command $B0 allows writing of data in the device's currently selected user zone (the procedure
for selecting a user zone is described below, see System WRITE: $B4).
The data byte address to be written is defined by Address 1 and Address 2 in the command. The value N defines how
many bytes are to be written. The maximum number of bytes that may be written is $10 corresponding to the EEPROM
page size. In anti-tearing mode the maximum value for N is $08 for all devices. A write in anti-tearing mode is activated
with the Set User Zone with anti-tearing command; all subsequent write operations to the user zone will be in anti-
tearing mode. A write may be started in the middle of an EEPROM page but should not extend past the end of the
page.
When a Write User Zone command is sent in Authentication mode or Encryption mode the data is saved in a buffer
until a cryptographic checksum is received. The host must send the checksum it has computed immediately after the
Write User Zone command. If the checksum is valid, CryptoMemory writes the data; if the checksum is incorrect the
data is discarded and the cryptographic engine is reset. If the host is not allowed to write in the zone, the device will not
acknowledge the N byte. After this command the host must perform ACK polling.
N data bytes
Number of bytes N
Command
Address 1
Address 2
Host
Data
Data
…
Atmel AT88SC0104/0204/0404/0808/CA
Device
®
CryptoMemory
®
devices will
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