Select GPIO with current supply capability of 5
mA. Figure 8-12 shows that the SCL, SDA lines and INT pin can be shared.
However, the function of the INT pin must be analyzed when
shared by multiple sensors. As an example, if the sensors are configured to generate
interrupt through the INT pin, the microcontroller needs to
read all the sensors to determine which specific one sending the interrupt. Take the
following steps sequentially to assign new I2C addresses to the four TMAG5173-Q1 shown in Figure 8-13:
- Turn on the GPIO#1 and wait until
tstart_power_up time is elapsed.
- Address the device#1 with
factory programmed address. Write to the I2C_ADDRESS register to assign a
new address.
- Turn on the GPIO#2 and wait
until tstart_power_up time is elapsed.
- Address the device#2 with
factory programmed address. Write to the I2C_ADDRESS register to assign a
new unique address.
- Turn on the GPIO#3 and wait
until tstart_power_up time is elapsed.
- Address the device#3 with
factory programmed address. Write to the I2C_ADDRESS register to assign a
new unique address.
- Turn on the GPIO#4 and wait
until tstart_power_up time is elapsed.
- Address the device#4 with
factory programmed address. Write to the I2C_ADDRESS register to assign a
new unique address.
Repeat the above steps if there is a power outage
or power-up reset condition.