SAM3X8E Atmel Corporation, SAM3X8E Datasheet - Page 720

• Manufacturer Part Number: SAM3X8E
• Manufacturer: Atmel Corporation

Figure 33-11. Master Write with One, Two or Three Bytes Internal Address and One Data Byte
Figure 33-12. Master Read with One, Two or Three Bytes Internal Address and One Data Byte
33.8.6.2
720
720
TWD
TWD
TWD
TWD
TWD
TWD
Three bytes internal address
Two bytes internal address
One byte internal address
Three bytes internal address
Two bytes internal address
One byte internal address
S
S
S
SAM3X/A
SAM3X/A
S
S
S
10-bit Slave Addressing
DADR
DADR
DADR
DADR
DADR
DADR
W
W
W
For a slave address higher than 7 bits, the user must configure the address size (IADRSZ) and
set the other slave address bits in the internal address register (TWI_IADR). The two remaining
Internal address bytes, IADR[15:8] and IADR[23:16] can be used the same as in 7-bit Slave
Addressing.
Example: Address a 10-bit device (10-bit device address is b1 b2 b3 b4 b5 b6 b7 b8 b9 b10)
Figure 33-13
the use of internal addresses to access the device.
Figure 33-13. Internal Address Usage
1. Program IADRSZ = 1,
2. Program DADR with 1 1 1 1 0 b1 b2 (b1 is the MSB of the 10-bit address, b2, etc.)
3. Program TWI_IADR with b3 b4 b5 b6 b7 b8 b9 b10 (b10 is the LSB of the 10-bit
W
W
W
A
A
A
address)
IADR(23:16)
A
A
A
IADR(15:8)
IADR(7:0)
below shows a byte write to an Atmel AT24LC512 EEPROM. This demonstrates
IADR(23:16)
IADR(15:8)
IADR(7:0)
R
S
T
A
T
M
S
B
Address
Device
A
A
A
0
IADR(15:8)
Sr
IADR(7:0)
A
A
A
S
B
L
W
W
R
T
E
R
I
/
DADR
C
A
K
WORD ADDRESS
IADR(15:8)
IADR(7:0)
M
S
B
DATA
FIRST
R
A
A
Sr
IADR(7:0)
A
A
A
A
A
C
K
WORD ADDRESS
DADR
SECOND
IADR(7:0)
P
DATA
DATA
A
L
S
B
Sr
R
C
A
K
A
A
N
A
DADR
DATA
DATA
P
P
DATA
DATA
11057A–ATARM–17-Feb-12
11057A–ATARM–17-Feb-12
A
C
K
R
N
O
S
T
P
P
A
N
A
P
P