STMicroelectronics STCF03, Руководство пользователя

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Introduction STCF03
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7.2.4 ADD pin
With this pin it is possible to select one of the 4 possible I
2
C slave addresses. No internal
pull-up nor pull-down is provided. The pin has to be connected either GND, V
I
, SCL or SDA
to select the desired I
2
C slave address (see Table 6. )
7.2.5 TMSK pin
This pin can be used to implement the TX masking function. This function has effect only for
Flash current settings higher than 200 mA (bit FDIM_3=1). Under this condition, when this
pin is pulled high by the P, the current flowing in the LED is forced at 200 mA typ. No internal
pull-up nor pull-down is provided: to be externally wired to GND if TX masking function is not
used.
7.3 I
2
C BUS interface
Data transmission from the main µP STCF03 and vice versa takes place through the 2 wires
I
2
C bus interface wires, consisting of the two lines SDA and SCL (pull-up resistors to a
positive supply voltage must be externally connected). The recommended maximum voltage
of these signals should be 3.0 V.
7.4 Data validity
As shown in Figure 4 , the data on the SDA line must be stable during the high period of the
clock. The HIGH and LOW state of the data line can only change when the clock signal on
the SCL line is LOW.
Table 7. Address table
ADD pin A7 A6 A5 A4 A3 A2 A1 A0
GND 0 1 1 0 0 0 0 R/W
VBAT 0 1 1 0 0 0 1 R/W
SDAL 0 1 1 0 0 1 0 R/W
SCL 0 1 1 0 0 1 1 R/W
Figure 4. Data validity on the I
2
C Bus