CAT6095_11 Datasheet, PDF (7/15 Pages) ON Semiconductor – Digital Output Temperature Sensor

CAT6095
Write Operations
Temperature Sensor Register Write
To write data to a TS register the Master creates a START
condition on the bus, and then sends out the appropriate
Slave address (with the R/W bit set to ‘0’), followed by an
address byte and two data bytes. The matching Slave will
acknowledge the Slave address, TS register address and the
TS register data (Figure 12). The Master then ends the
session by creating a STOP condition on the bus. The STOP
completes the TS register update. Note that all registers in
the TS are ‘volatile’ meaning any data contained in them is
lost when power is removed from the chip.
Read Operations
Immediate Read
Upon power-up, the Temperature Sensor (TS) address
counter is initialized to 00h. The TS address counter will
thus point to the Capability Register. This address counter
may be updated by subsequent operations.
A CAT6095 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 TS register address counter. The Master stops this
transmission by responding with NoACK, followed by a
STOP (Figure 13).
Selective Read
The Read operation can be started at an address different
from the one stored in the address counter, 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 (Figure 14).
BUS ACTIVITY: S
T
A
MASTER
R
T
SDA LINE S
SLAVE
SLAVE
ADDRESS
REGISTER
ADDRESS
DATA (MSB)
S
T
DATA (LSB)
O
P
P
A
A
A
A
C
C
C
C
K
K
K
K
Figure 12. Temperature Sensor Register Write
BUS ACTIVITY: S
T
A
MASTER ^R
T
SDA LINE S
SLAVE
SLAVE
ADDRESS
A
C
K
A
C
K
DATA (MSB)
N
OS
AT
CO
KP
P
DATA (LSB)
Figure 13. Immediate Read
BUS ACTIVITY: S
T
A
MASTER R
T
SDA LINE S
SLAVE
S
T
SLAVE
REGISTER A _SLAVE
A
ADDRESS
ADDRESS
R
T
ADDRESS
C
K
S
A
A
C
C
K
K
A
C ^{DATA (MSB)}
K
Figure 14. Selective Read
N
OS
AT
CO
KP
P
DATA (LSB)
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