ATSHA204 ATMEL [ATMEL Corporation], ATSHA204 Datasheet - Page 35

• Manufacturer Part Number: ATSHA204
• Description: Atmel CryptoAuthentication
• Manufacturer: ATMEL [ATMEL Corporation]

8.1.4
Address Encoding
The Read and Write commands include a single address in Param2 that indicates the memory to be accessed. All Reads and
Writes are in units of four bytes (one word). The most-significant byte of a legal ATSHA204 address is always zero. All unused
address bits should always be set to zero. The least-significant bits in the address describe the offset to the first word to be
accessed within the block/slot, while the upper bits specify the block/slot number per the table below:
Table 8-5.
Within each zone, there are various access restrictions per the table below:
Table 8-6.
In the table below, “Byte Address” is the byte address within the data zone for the first byte in the respective slot. Because all
Reads and Writes with the ATSHA204 are performed on a word (4-byte or 32-bit) basis, the word address in the table below
should be used for the address parameter passed to the Read and Write commands.
Table 8-7.
Zone
Config
OTP
Data
Zone
Config
OTP
Data
Slot #
0
1
2
3
4
5
6
7
Legal Block/Slot
Address Encoding (Param2)
Legal Block/slot Values
Data Zone Slots
(inclusive)
0-15
Byte 1
Unused
Bits 0  7
Bits 0  7
Bits 0  7
0-2
0-1
Byte Address
0x00C0
0x0000
0x0020
0x0040
0x0060
0x0080
0x00A0
0x00E0
(Hex)
Notes
Addresses below 16 (block 0, offset 16) and above 87 (block 2, offset 23) can never be written.
Addresses above 87 can never be read. Both 4- and 32-byte reads/writes are permitted
When OTPmode is read-only, all offsets in both blocks are available to use with 4- or 32-byte
reads.
If OTPmode is consumption, then writes are also permitted to all offsets.
See Section 2.1.3 if OTPmode is Legacy.
All offsets in all slots available for both read and write.
4-byte access permitted on a particular slot only if SlotConfig.IsSecret is zero.
Byte 0
Unused
Bits 5  7
Bits 4  7
Bit 7
Word Address
0x0000
0x0008
0x0010
0x0018
0x0020
0x0028
0x0030
0x0038
(Hex)
Block/Slot
Bits 3  4
Bit 3
Bits 3  6
Slot #
10
11
12
13
14
15
8
9
Offset
Bits 0  2
Bits 0  2
Bits 0  2
Byte Address
0x01A0
0x01C0
0x01E0
0x0100
0x0120
0x0140
0x0160
0x0180
(Hex)
Atmel ATSHA204 [DATASHEET]
Word Address
0x007F
0x0040
0x0048
0x0050
0x0058
0x0060
0x0068
0x0070
(Hex)
8740D−CRYPTO−3/12
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