Rainbow Electronics AT91CAP9S250A - Manual (Page 491)

491
6264A–CAP–21-May-07
AT91CAP9S500A/AT91CAP9S250A
Example: Address a 10-bit device (10-bit device address is b1 b2 b3 b4 b5 b6 b7 b8 b9 b10)
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
address)
Figure 34-13 below shows a byte write to an Atmel AT24LC512 EEPROM. This demonstrates
the use of internal addresses to access the device.
Figure 34-13. Internal Address Usage
S
T
A
R
T
M
S
B
Device
Address
0
L
S
B
R
/
W
A
C
K M
S
B
W
R
I
T
E
A
C
K A
C
K L
S
B
A
C
K
FIRST
WORD ADDRESS
SECOND
WORD ADDRESS DATA
S
T
O
P