Datasheet

26
Atmel AT30TSE002B [DATASHEET]
8711G–SEEPR–5/12
12. TS Write Operations
Writing to the AT30TSE002B Temperature register set is accomplished through a modified write operation for two data
bytes. To maintain 2-wire compatibility, the 16-bit register is accessed through a pointer register, requiring the write
sequence to include an address pointer in addition to the device address. This indicates the storage location for the next
two bytes received. Table 12-1 shows an entire write transaction on the bus.
Figure 12-1. TS Register Write Operation
12.1 TS Read Operations
Reading data from the TS may be accomplished in one of two ways:
 If the location latched in the pointer register is correct (for normal operation it is expected the same address will be
read repeatedly for temperature), the read sequence may consist of a device address from the bus master
followed by two bytes of data from the device; or
 The pointer register is loaded with the correct register address, and the data is read. The sequence to preset the
pointer register is shown in Figure 12-4, and the preset pointer read is shown in Figure 12-3. If it is desired to read
random address each cycle, the complete pointer write, word read sequence is shown in Figure 12-4.
The data byte has the most significant bit first. At the end of a read, this device can accept either Acknowledge (ACK) or
No Acknowledge (No ACK) from the Master (No Acknowledge is typically used as a signal for the slave that the Master
has read its last byte).
Figure 12-2. Write to Pointer Register
Figure 12-3. Preset Pointer Register Word Read
0011A2A1A0
S
T
A
R
T
Device
Address
R
/
W
A
C
K
A
C
K
A
C
K
A
C
K
Register
Pointer
S
T
O
P
W
R
I
T
E
Data
MSB
Data
LSB
0011A2A1A0
S
T
A
R
T
R
/
W
A
C
K
A
C
K
W
S
T
O
P
R
I
T
E
Device
Address
Register
Pointer
0011A2A1A0
S
T
A
R
T
R
/
W
A
C
K
A
C
K
N
O
A
C
K
Data
MSB
Data
LSB
S
T
O
P
R
E
A
D
Device
Address