CAT34TS02_14 Datasheet, PDF (10/21 Pages) ON Semiconductor – Digital Output Temperature Sensor

CAT34TS02
BUS ACTIVITY: ^S
T
A
MASTER R
T
SDA LINE S
SLAVE
SPD
SLAVE
ADDRESS
BYTE
ADDRESS (n)
DATA n
DATA n+1
A
A
A
A
C
C
C
C
K
K
K
K
NOTE: In this example n = XXXX 0000(B); X = 1 or 0
Figure 27. EEPROM Page Write
S
T
DATA n+P ^O
P
P
A
C
K
Read Operations
Immediate Read
Upon power−up, the address counters for both the
Temperature Sensor (TS) and on−board EEPROM are
initialized to 00h. The TS address counter will thus point to
the Capability Register and the EEPROM address counter
will point to the first location in memory. The two address
counters may be updated by subsequent operations.
A CAT34TS02 presented with a Slave address containing
a ‘1’ in the R/W position will acknowledge the Slave address
and will then start transmitting data being pointed at by the
current EEPROM data or respectively TS register address
counter. The Master stops this transmission by responding
with NoACK, followed by a STOP (Figures 28a, 28b).
Selective Read
The Read operation can be started at an address different
from the one stored in the respective address counters, by
preceding the Immediate Read sequence with a ‘data less’
Write operation. The Master sends out a START, Slave
address and address byte, but rather than following up with
data (as in a Write operation), the Master then issues another
START and continuous with an Immediate Read sequence
(Figures 29a, 29b).
Sequential EEPROM Read
EEPROM data can be read out indefinitely, as long as the
Master responds with ACK (Figure 30). The internal address
count is automatically incremented after every data byte sent
to the bus. If the end of memory is reached during continuous
Read, then the address counter ‘wraps−around’ to beginning
of memory, etc. Sequential Read works with either
Immediate Read or Selective Read, the only difference
being that in the latter case the starting address is
intentionally updated.
BUS ACTIVITY: ^S
N
T
SPD
A
SLAVE
OS
AT
MASTER R _ADDRESS
T
CO
KP
SDA LINE S
P
SLAVE
A
C
DATA
K
Figure 28a. EEPROM Immediate Read
BUS ACTIVITY: S
T
A
MASTER ^R
T
SDA LINE S
TS
SLAVE
ADDRESS
N
OS
A
AT
C
CO
K
KP
P
SLAVE
A
C ^{DATA (MSB)}
K
DATA (LSB)
Figure 28b. Temperature Sensor Immediate Read
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