查看“指间ESP光敏与Mic传感器操作”的源代码

{| style="width: 800px;"
|-
|
<p style="color: #4F4E4E;font-size:220%">'''指间ESP光敏与Mic传感器操作'''</p>
<br>
指间ESP开发板板载了mic声音传感器和光敏传感器，分别对应IO37、IO38，该示例展示了如何读取传感器模拟值。在指间板中，ADC读取的电压值以毫伏单位输出，“2000”为2000mV即2V。
<br>
<br>
<source lang="c++">
import machine, display
from machine import Pin, ADC

adcmic = ADC(Pin(37))
adclight = ADC(Pin(38))

bkcolor = 0x333333

tft = display.TFT()
tft.init(tft.ST7789)

tft.clear()
tft.rect(0, 0, 240, 240, bkcolor, bkcolor)

def mapTo(x, in_min, in_max, out_min, out_max):
    return int((x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min)

while True:
    micval = adcmic.read()
    lightval = adclight.read()
    # mic
    tft.line(195, 62, 215, 62, 0xFFFFFF)
    tft.line(205, 53, 205, 63, 0xFFFFFF)
    tft.ellipse(205, 43, 10, 10, 12, 0xFFFFFF, bkcolor)
    tft.roundrect(198, 15, 15, 32, 6, 0xFFFFFF, bkcolor)

    tft.roundrect(
        199,
        47 - mapTo(micval, 142, 3200, 6, 32),
        13,
        mapTo(micval, 142, 3200, 6, 32) - 1,
        6,
        bkcolor,
        0xFFFFFF,
    )
    tft.rect(185, 68, 50, 15, bkcolor, bkcolor)
    tft.text(185, 70, str(micval), 0xFFFFFF, transparent=True)

    # light
    tft.line(25, 57, 45, 57, 0xFFFFFF)
    tft.line(35, 47, 35, 58, 0xFFFFFF)
    tft.line(27, 55, 21, 61, 0xFFFFFF)
    tft.line(38, 55, 32, 61, 0xFFFFFF)
    tft.line(47, 55, 41, 61, 0xFFFFFF)
    tft.roundrect(28, 15, 15, 32, 6, 0xFFFFFF, bkcolor)  # light
    tft.roundrect(
        29,
        47 - mapTo(lightval, 142, 3200, 6, 32),
        13,
        mapTo(lightval, 142, 3200, 6, 32) - 1,
        6,
        bkcolor,
        0xFFFFFF,
    )
    tft.rect(15, 68, 50, 15, bkcolor, bkcolor)
    tft.text(15, 70, str(lightval), 0xFFFFFF, transparent=True)
</source>
**该程序使用板载TFT屏幕画出两个圆角矩形用于标识状态，非按下时为青色，按下时为黄色。
[[File:Tftadc.png|600px|center]]
程序详解：
<br>
import为引用所需文件，包括display（屏幕驱动），Pin（IO口驱动）
<source lang="c++">
import machine, display 
from machine import Pin
</source>
之后声明ADC，并命名为adcmic与adclight
<source lang="c++">
adcmic = ADC(Pin(37))
adclight = ADC(Pin(38))
</source>

初始化TFT并使用背景色"bkcolor"填充屏幕
<source lang="c++">
bkcolor = 0x333333

tft = display.TFT()
tft.init(tft.ST7789)

tft.clear()
tft.rect(0, 0, 240, 240, bkcolor, bkcolor)
</source>
自制map函数，用于将ADC值映射到绘制图形的尺寸上
<source lang="c++">
def mapTo(x, in_min, in_max, out_min, out_max):
    return int((x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min)
</source>
读取ADC
<source lang="c++">
    micval = adcmic.read()
    lightval = adclight.read()
</source>
绘制两个麦克风图形并将ADC数值显示在下面，具体图形绘制函数参考 : [https://github.com/loboris/MicroPython_ESP32_psRAM_LoBo/wiki/display TFT图形绘制Wiki]
<source lang="c++">
    tft.line(195, 62, 215, 62, 0xFFFFFF)
    tft.line(205, 53, 205, 63, 0xFFFFFF)
    tft.ellipse(205, 43, 10, 10, 12, 0xFFFFFF, bkcolor)
    tft.roundrect(198, 15, 15, 32, 6, 0xFFFFFF, bkcolor)

    tft.roundrect(
        199,
        47 - mapTo(micval, 142, 3200, 6, 32),
        13,
        mapTo(micval, 142, 3200, 6, 32) - 1,
        6,
        bkcolor,
        0xFFFFFF,
    )
    tft.rect(185, 68, 50, 15, bkcolor, bkcolor)
    tft.text(185, 70, str(micval), 0xFFFFFF, transparent=True)

    # light
    tft.line(25, 57, 45, 57, 0xFFFFFF)
    tft.line(35, 47, 35, 58, 0xFFFFFF)
    tft.line(27, 55, 21, 61, 0xFFFFFF)
    tft.line(38, 55, 32, 61, 0xFFFFFF)
    tft.line(47, 55, 41, 61, 0xFFFFFF)
    tft.roundrect(28, 15, 15, 32, 6, 0xFFFFFF, bkcolor)  # light
    tft.roundrect(
        29,
        47 - mapTo(lightval, 142, 3200, 6, 32),
        13,
        mapTo(lightval, 142, 3200, 6, 32) - 1,
        6,
        bkcolor,
        0xFFFFFF,
    )
    tft.rect(15, 68, 50, 15, bkcolor, bkcolor)
    tft.text(15, 70, str(lightval), 0xFFFFFF, transparent=True)
</source>
<br>
|}
<br>
<br>
<p style="font-size:115%">[[指间ESP开发板编程手册|返回指间ESP开发板编程手册界面]]</p>