AT88SC0104C datasheet(32/58 Pages) ATMEL

32 / 58 page

5210B–SMIC–11/08

AT88SC0104/0204/0404/0808/1616/3216/6416/12816/25616C

Figure 7-4.

Write User Zone

7.6.2

Read User Zone: $B2

7.6.2.1

Functional

Figure 7-5.

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 below under Section 7.6.3.4 on

page 31).

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 how-

ever may cease clocking the device and end the transmission with a NACK and STOP at

anytime 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 7-6.

Read User Zone

Device

Read Command

Address 1

Address 2

Number of Bytes N

Host

N data bytes

Data

...

Data

Command

Address 1

Address 2

Data

Data x N

1011 0010

xxxx xxxx

d7--- ---d0

AT88SC0104C Datasheet(PDF) 32 Page - ATMEL Corporation