526互联

7. 模数转换

发布时间 2023-03-24 15:13:57作者: 残影0无痕

ADC0832.py

#!/usr/bin/env python
#
#       This is a program for all ADC Module. It 
#   convert analog singnal to digital signal.
#
#       This program is most analog signal modules' 
#   dependency. Use it like this:
#       `import ADC0832`
#       `sig = ADC0832.getResult(chn)`
#
#   *'chn' should be 0 or 1 represent for ch0 or ch1
#   on ADC0832
#       
#         ACD1302                 Pi
#           CS ---------------- Pin 11
#           CLK --------------- Pin 12
#           DI ---------------- Pin 13

#           VCC ----------------- 3.3V
#           GND ------------------ GND
#

import RPi.GPIO as GPIO
import wiringpi
import time

ADC_CS  = 17 #11
ADC_CLK = 18 #12
ADC_DIO = 27 #13

# using default pins for backwards compatibility
def setup(cs=17,clk=18,dio=27): #11,12,13
    global ADC_CS, ADC_CLK, ADC_DIO
    ADC_CS=cs
    ADC_CLK=clk
    ADC_DIO=dio
    GPIO.setwarnings(False)
    GPIO.setmode(GPIO.BCM)          # Number GPIOs by its physical location
    GPIO.setup(ADC_CS, GPIO.OUT)        # Set pins' mode is output
    GPIO.setup(ADC_CLK, GPIO.OUT)       # Set pins' mode is output

def destroy():
    GPIO.cleanup()

# using channel = 0 as default for backwards compatibility
def getResult(channel=0):                   # Get ADC result, input channal
    GPIO.setup(ADC_DIO, GPIO.OUT)
    GPIO.output(ADC_CS, 0)
        
    GPIO.output(ADC_CLK, 0)
    GPIO.output(ADC_DIO, 1); wiringpi.delayMicroseconds(2)
    GPIO.output(ADC_CLK, 1);  wiringpi.delayMicroseconds(2)
    GPIO.output(ADC_CLK, 0)

    GPIO.output(ADC_DIO, 1);  wiringpi.delayMicroseconds(2)
    GPIO.output(ADC_CLK, 1);  wiringpi.delayMicroseconds(2)
    GPIO.output(ADC_CLK, 0)

    GPIO.output(ADC_DIO, channel);  wiringpi.delayMicroseconds(2)

    GPIO.output(ADC_CLK, 1)
    GPIO.output(ADC_DIO, 1);  wiringpi.delayMicroseconds(2)
    GPIO.output(ADC_CLK, 0)
    GPIO.output(ADC_DIO, 1);  wiringpi.delayMicroseconds(2)

    dat1 = 0
    for i in range(0, 8):
        GPIO.output(ADC_CLK, 1);  wiringpi.delayMicroseconds(2)
        GPIO.output(ADC_CLK, 0);  wiringpi.delayMicroseconds(2)
        GPIO.setup(ADC_DIO, GPIO.IN)
        dat1 = dat1 << 1 | GPIO.input(ADC_DIO)  
    
    dat2 = 0
    for i in range(0, 8):
        dat2 = dat2 | GPIO.input(ADC_DIO) << i
        GPIO.output(ADC_CLK, 1);  wiringpi.delayMicroseconds(2)
        GPIO.output(ADC_CLK, 0);  wiringpi.delayMicroseconds(2)
    
    GPIO.output(ADC_CS, 1)
    GPIO.setup(ADC_DIO, GPIO.OUT)

    if dat1 == dat2:
        return dat1
    else:
        return 0

def getResult1():
    return getResult(1)


def loop():
    while True:
        res0 = getResult(0)
        res1 = getResult(1)
        print ('res0 = %d, res1 = %d' % (res0,res1))
        time.sleep(0.4)

if __name__ == '__main__':      # Program start from here
    setup()
    try:
        loop()
    except KeyboardInterrupt:   # When 'Ctrl+C' is pressed, the child program destroy() will be  executed.
        destroy()

measure_plt.py

import ADC0832
import time
import numpy as np
import matplotlib.pyplot as plt
def init():
    ADC0832.setup()
def loop():
    n=0
    i=0
    y=[]
    x=[]
    t=time.process_time() 

    while n<10:
        digitalVal=ADC0832.getResult()
        y.append(3.3*float(digitalVal)/255)
        x.append(time.process_time()) 
        n=n+1
    #plt.axis([0.1,0.2,0.4,0.8])
    #前后两组参数分别表示x、y轴范围
    #等价于plt.xlim(0.1,0.2) plt.ylim(0.4,0.8)
    plt.plot(x,y,'-o')
    while i<10:
        x1="%.3f"%x[i]
        y1="%.2f"%y[i]
        text='{'+str(x1)+','+str(y1)+'}'
        plt.text(x[i],y[i],text)
        i=i+1
    plt.show()
if __name__=='__main__':
    init()
    loop()
    ADC0832.destroy()
    print("The End")

measure_sin.py

import ADC0832
import time
import numpy as np
import matplotlib.pyplot as plt
def init():
    ADC0832.setup()
def loop():
    n=0
    t=0
    y=[]
    x=[]
    while n<1000:
        digitalVal=ADC0832.getResult()
        y.append(3.3*float(digitalVal)/255)
        x.append(time.perf_counter()) 
        # or time.process_time()
        n=n+1
    t=time.perf_counter()-t 
    # or time.process_time()
    plt.plot(x,y)
    plt.show()
if __name__=='__main__':
    init()
    loop()
    ADC0832.destroy()
    print("The End")

measure_V.py

import ADC0832
import time
def init():
    ADC0832.setup()
    #def setup(cs=11,clk=12,dio=13):
    #   global ADC_CS, ADC_CLK, ADC_DIO
    #   ADC_CS=cs
    #   ADC_CLK=clk
    #   ADC_DIO=dio
    #   GPIO.setwarnings(False)
    #   GPIO.setmode(GPIO.BOARD)            
    #   GPIO.setup(ADC_CS, GPIO.OUT)        
    #   GPIO.setup(ADC_CLK, GPIO.OUT)       
def loop():
    while True:
        digitalVal=ADC0832.getResult()
        # Get ADC result, input channal
        # getResult()函数代码实现ADC0832工作原理
        # 得到0~255之间的一个数
        # 详细参见ADC0832.py
        print(3.3*float(digitalVal)/255)
        # 转换为电压量
        time.sleep(0.2)
if __name__=='__main__':
    init()
    try:
        loop()
    except KeyboardInterrupt:
        ADC0832.destroy()#调用GPIO.cleanup
        print("The end!")