DS75LX: Digital Thermometer and Thermostat with Extended Addressing
Figure 8. 2-Wire Interface Timing
(DS75LX)
(DS75LX)
A
D2D6
D5 D4
D3
D1
D0
WA
0
00
0
0
00
1AD7
Address ByteSTART
SCL
SDA
ACK
Pointer Byte
P
Data Byte
(from Master)
STOP
ACK
ACK
(DS75LX)
A
D2D6
D5 D4
D3
D1
D0
WA
0
00
0
0
00
1
0
00
0
0
00
1AD7
b) Write to the Configuration Register
S
Address ByteSTART
SCL
SDA
ACK
Pointer Byte
P
Data Byte
(from Master)
STOP
ACK
ACK
c) Write to the T
OS
or T
HYST
Register
SCL
SDA
W
A
Address Byte
START
ACK
(DS75LX)
A
0
0
000
0
P1
P0
Pointer Byte
ACK
(DS75LX)
D4
D6
D5
D3
D2 D0D7D6 D5 D4
D3
D2 D1
D0
D7
A
D1
P
LS Data Byte
(from Master)
A
MS Data Byte
(from Master)
STOP
ACK
(DS75LX)
ACK
(DS75LX)
c) Write to the T
OS
or T
HYST
Register
SCL
SDA
S
W
A
Address Byte
START
ACK
A
0
0
000
0
P1
P0
0
0
000
0
P1
P0
Pointer Byte
ACK
D4
D6
D5
D3
D2 D0D7D6 D5 D4
D3
D2 D1
D0
D7
A
D1
P
LS Data Byte
(from Master)
A
MS Data Byte
(from Master)
STOP
ACK ACK
d) Read Single Byte (new pointer location)
(DS75LX)
START
(from DS75LX)
(Master)
(DS75LX )
(DS75LX)
N
A
0
W
0
00
0
0
D6 D5
D4
D3
D2 D1 D0 P
D7
RA
ACK
Repeat
SCL
SDA
Address Byte
START
Pointer Byte
Data Byte
STOP
NACKAddress Byte
ACK
ACK
P1 P0
N
A
0
S
W
0
00
A
0
0
D6 D5
D4
D3
D2 D1 D0 P
D7
S
RA
ACK
Repeat
SCL
SDA
Address Byte
START
Pointer Byte
Data Byte
STOP
NACKAddress Byte
ACK
ACK
P1 P0P1 P0
on)
SCL
SDA
START
N
D6
D5
D4
D3
D2 D1 D0 P
D7
R
Data Byte
(from DS75LX)
STOP
NACK
(Master)
Address Byte ACK
(DS75LX)
S
e) Read From the Configuration Register (current pointer location)
SCL
SDA
START
N
D6
D5
D4
D3
D2 D1 D0 P
D7
R
Data Byte
STOP
NACK
(Master)
Address Byte ACK
N
D6
D5
D4
D3
D2 D1 D0 P
D7
RA
Data Byte
STOP
NACK
(Master)
Address Byte ACK
a) Read 2-Bytes From the Temperature, T
OS
or T
HYST
Register (current pointer location)
SCL
SDA
START
A
D6 D5
D4
D3 D2 D1 D0D7
1
1
0RA
MS Data Byte
(from DS75LX)
ACK
(Master)
Address Byte ACK
(DS75LX)
N
D6
D5
D4
D3
D2 D1
D0
P
D7
LS Data Byte
(from DS75LX)
STOP
NACK
(Master)
S
Bytes From the Temperature, T
OS
or T
HYST
Register (current pointer location)
SCL
SDA
START
A
D6 D5
D4
D3 D2 D1 D0D7
1
1
0
0
RA
MS Data Byte
ACK
(Master)
Address Byte ACK
N
D6
D5
D4
D3
D2 D1
D0
P
D7
LS Data Byte
STOP
NACK
(Master)
1
1
0
1
1
0
0
1
1
0
1
1
0
0
1
1
0
1
1
0
0
1
1
0
1
1
0
0
1
1
0
1
1
0
0
An address byte value of 1110010 corresponds to A0 connected to V
DD
, A1 connected to GND, and A2 floating.
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