Running the demonstration
UM1011
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Doc ID 18064 Rev 1
2.7.7 Thermometer
The STM32F100ZET6 microcontroller has two embedded I
2
C peripherals that can be
connected to any device supporting the I
2
C protocol including the System management bus
(SMBus) mode. An STLM75 (or a compatible device) I
2
C temperature sensor is mounted on
the STM32100E-EVAL board and used to capture the external temperature (-55°C to
+125°C).
When the
Thermometer
submenu is selected, the message shown in
Figure 52
is
displayed on the LCD.
Figure 52.
Thermometer submenu selected
Once you select the
Temperature
submenu, the temperature value is displayed in Celsius
and Fahrenheit as shown in
Figure 53
.
Press any key to return to the
Thermometer
submenu.
Figure 53.
Temperature display
The temperature variations can be monitored easily using the STM32 I2C SMBus feature.
This is managed by the SMBus Alert, which generates a dedicated interrupt to inform the
system that the temperature is out of the selected range. This can be very useful for
systems where the increase of temperature needs an immediate intervention, like in motor
control, medical systems, etc.
If the temperature exceeds the over-limit high value (TEMPERATURE_TOS: Over Limit
Temperature), the SMBus Alert interrupt is generated and the following warning message is
displayed on the LCD screen:
Thermometer
Return
Temperature
Temperature
+xxx.x C
+xxx.x F
