AT88SC0104CA_11 ATMEL [ATMEL Corporation], AT88SC0104CA_11 Datasheet - Page 33

• Manufacturer Part Number: AT88SC0104CA_11
• Description: Atmel CryptoMemory Specification Datasheet
• Manufacturer: ATMEL [ATMEL Corporation]

8.9
8.9.1
Read User Zone: $B2
Functional
Figure 8-9. Read User Zone Command Functional Description
The read user zone command $B2 allows reading of data from the device's currently selected user zone (the procedure for
selecting a user zone is described in Section 8.10, System Write: $B4).
The data byte address to be read is defined by Address 1 and Address 2 in the command and is internally incremented
following the transmission of each data byte. The value N defines how many bytes CryptoMemory will read, a value of zero will
result in 256 bytes read. The host however, may cease clocking the device and end the transmission with a NACK and stop at
any time prior to receiving all N bytes. During a read operation the address will "roll over" from the last byte of the current
zone, to the first byte of the same zone.
If the host is not allowed to read the zone, the device will not acknowledge the N byte.
Figure 8-10. Read User Zone Command Structure
S
T
A
R
T
Command
1011 0010
C
A
K
Host
Read Command
Address 1
Address 2
Number of bytes N
Address 1
xxxx xxxx
A
C
K
Address 2
xxxx xxxx
Device
Data
…
Data
A
C
K
Atmel AT88SC0104CA/0204CA/0404CA/0808CA [Datasheet]
xxxx xxxx
N
C
A
K
d7--- ---d0
N data bytes
Data
A
C
K
Data x N
d7--- ---d0
N
A
C
K
O
S
T
P
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