[作品提交] 【得捷电子Follow me第3期】任务5：使用外部传感器|电阻测温度

alanlan86 2023-11-19 10:50 楼主

#准备工作
- ESP32-C3 XIAO开发板一块
![](https://files.seeedstudio.com/wiki/XIAO_WiFi/pin_map-2.png)
- 测温传感器扩展板一块
![](https://files.seeedstudio.com/wiki/Grove-Temperature_Sensor/img/Temperature1.jpg)
- SSD1306 OLED扩展显示板
![](https://files.seeedstudio.com/wiki/Grove-OLED-Display-0.96-SSD1315-/img/Grove-OLED-Displey-0.96-SSD1315-pin.jpg)

#硬件
- 将温度传感器链接到GPIO2（A0/D0)引脚，输入电源VCC和GND
- 关于温度扩展板的原理图可以获取：[温度传感器原理图](https://wiki.seeedstudio.com/Grove-Temperature_Sensor/ "温度传感器原理图")
- OLED接入I2C SCL=7 SDA=6

#软件

- 通过ADC采集LM358输出的温度传感器电压，然后通过电压计算电阻值，并通过对数计算，得到温度值

```python
from machine import ADC
from machine import Pin, SoftI2C
import ssd1306
from time import sleep
import time
import math

# ESP32 Pin assignment
i2c = SoftI2C(scl=Pin(7), sda=Pin(6))  # Adjust the Pin numbers based on your connections

oled_width = 128
oled_height = 64
oled = ssd1306.SSD1306_I2C(oled_width, oled_height, i2c)

oled.fill(0)
oled.text("Starting up...", 0, 0)
oled.show()

bValue=3975
adc = ADC(Pin(2))        # create an ADC object acting on a pin
adc.atten(ADC.ATTN_11DB)
adc.width(ADC.WIDTH_12BIT)  #4095

while True:
    val = adc.read()
    print("adc=", val)

# Transform the ADC data into the data of Arduino platform.
    resistance=(float)(4095-val)*10000/val; #get the resistance of the sensor;
    print("res=", resistance)
    
    temperature = round((float)(1 / (math.log(resistance / 10000) / bValue + 1 / 298.15) - 273.15), 2)
    print("temperature=", temperature);
    
    oled.fill(0)
    oled.text("ESP32 XIAO Sensor", 0, 4)
    oled.text('resistance:{:.2f}'.format(resistance), 0, 24)
    oled.text('temperature:{:.2f}'.format(temperature), 0, 32)
    oled.show()
    time.sleep_ms(2000)
```

#调试

<div id="player_d93b159133057a5e03e38946e15db4cc0" class="localvideo-box"></div><div class="localvideo-title">任务5扩展传感器</div><br/>