TMP91C824
91C824-157
3.10.5
Control in I
2
C Bus Mode
(1) Acknowledge Mode Specification
Set the SBI0CR1<ACK> to 1 for operation in the acknowledge mode. The TMP91C824F generates
an additional clock pulse for an Acknowledge signal when operating in Master Mode, it counts a
clock pulse for an acknowledge signal when operating in the slave mode.
In the transmitter mode
during the clock pulse cycle, the SDA pin is released in order to receive the acknowledge signal
from the receiver. In the receiver mode during the clock pulse cycle, the SDA pin is set to the Low in
order to generate the acknowledge signal.
Clear the <ACK> to 0 for operation in the Non-Acknowledge Mode, The TMP91C824F does not
generate a clock pulse for the Acknowledge signal when operating in the Master Mode, and it does
not count a clock pulse as an Acknowledge signal when operating in Slave Mode.
(2) Number of transfer bits
The SBI0CR1<BC2 to BC0>
is used to select a number of bits for next transmitting and receiving
data.
Since the <BC2 to BC0> is cleared to 000 as a start condition, a slave address and direction bit
transmission are executed in 8 bits. Other than these, the <BC2 to 0> retains a specified value.
(3) Serial
clock
①
Clock
source
The SBI0CR1 <SCK2 to SCK0> is used to select a maximum transfer frequency outputted on the
SCL pin in Master Mode.
t
HIGH
t
LOW
1/fscl
t
LOW
= 2
n
/f
SBI
t
HIGH
= 2
n
/f
SBI
+
8/f
SBI
fscl = 1/(t
Low
+
t
HIGH
)
SBI0CR1 <SCK2
∼
SCK0>
n
000
001
010
011
100
101
110
5
6
7
8
9
10
11
=
f
SBI
2
n
+
8
Figure 3.10.7
Clock Source