STMicroelectronics STCF03, Руководство пользователя

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Introduction STCF03
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7.11 Reading from a single register
The reading operation starts with a START bit followed by the 7 bit device address of
STCF03. The 8
th
bit is the R/W bit, which is 0 in this case. STCF03 confirms the receiving of
the a R/W bit by an acknowledge pulse. The address of the register which should
be read is sent afterwards and confirmed again by an acknowledge pulse of STCF03 again.
Then the master generates a START bit again and sends the device address followed by the
R/W bit, which is 1 now. STCF03 confirms the receiving of the a R/W bit by an
acknowledge pulse and starts to send the data to the master. No acknowledge pulse from
the master is required after receiving the data. Then the master generates a STOP bit to
terminate the communication. See
Figure 10
7.12 Reading from multiple registers with incremental addressing
Reading from multiple registers starts in the same way like reading from a single register. As
soon as the first register is read, the register address is automatically increased. If the
master generates an acknowledge pulse after receiving the data from the first register, then
reading of the next register can start immediately without sending the device address and
Figure 9. Writing to multiple register with incremental addressing
S
T
A
R
T
DEVICE
ADDRESS
7 bits
A
C
K
W
R
I
T
E
M
S
B
L
S
B R
/
W
A
C
K
ADDRESS OF
REGISTER i DATA i
A
C
K A
C
K S
T
O
P M
S
B
M
S
B
L
S
B L
S
B
DATA i+1
A
C
K L
S
B
DATA i+2
A
C
K L
S
B
DATA i+2
L
S
B
DATA i+n
A
C
K M
S
B
M
S
B
M
S
B
M
S
B
M
S
B
A
C
K L
S
B
SDA LINE
S
T
A
R
T
DEVICE
ADDRESS
7 bits
A
C
K
W
R
I
T
E
M
S
B
L
S
B R
/
W
A
C
K
ADDRESS OF
REGISTER i DATA i
A
C
K A
C
K S
T
O
P M
S
B
M
S
B
L
S
B L
S
B
DATA i+1
A
C
K L
S
B
DATA i+2
A
C
K L
S
B
DATA i+2
L
S
B
DATA i+n
A
C
K M
S
B
M
S
B
M
S
B
M
S
B
M
S
B
A
C
K L
S
B S
T
A
R
T
DEVICE
ADDRESS
7 bits
A
C
K
W
R
I
T
E
M
S
B
L
S
B R
/
W
A
C
K
ADDRESS OF
REGISTER i DATA i
A
C
K A
C
K S
T
O
P M
S
B
M
S
B
L
S
B L
S
B
DATA i+1
A
C
K L
S
B
DATA i+2
A
C
K L
S
B
DATA i+2
L
S
B
DATA i+n
A
C
K M
S
B
M
S
B
M
S
B
M
S
B
M
S
B
A
C
K L
S
B
SDA LINE
Figure 10. Reading from a single register
S
T
A
R
T
DEVICE
ADDRESS
7 bits
A
C
K
W
R
I
T
E
M
S
B L
S
B R
/
W
ADDRESS
OF
REGISTER
A
C
K M
S
B L
S
B S
T
A
R
T A
C
K R
/
W
R
E
A
D
DEVICE
ADDRESS
7 bits
DATA
L
S
B S
T
O
P N
O
A
C
K
SDA LINE
S
T
A
R
T
DEVICE
ADDRESS
7 bits
A
C
K
W
R
I
T
E
M
S
B L
S
B R
/
W
ADDRESS
OF
REGISTER
A
C
K M
S
B L
S
B S
T
A
R
T A
C
K R
/
W
R
E
A
D
DEVICE
ADDRESS
7 bits
DATA
L
S
B S
T
O
P N
O
A
C
K
SDA LINE