使用SPI位冲击的Arduino上的多个模数转换器

时间:2013-11-10 07:45:56

标签: c arduino microcontroller spi analog-digital-converter

我正在使用Nano Arduino(ATMega 328)与基于this code的两个12位MCP3208 ADC芯片进行通信。我有另一个设备(LED驱动器TLC5940)连接到本页建议的引脚,但由于我使用位敲击,我使用的引脚无关紧要。因此,我的配置与上面的示例相同,只是:

    For ADC 1:
    CLK -> Arduino D6
    DOUT (MISO) -> Arduino D5
    DIN (MOSI) -> Arduino D12
    SS -> Arduino D7

    For ADC 2:
    CLK -> Arduino D6
    DOUT (MISO) -> Arduino D5
    DIN (MOSI) -> Arduino D12
    SS -> Arduino D8

所以,问题是我从ADC 1获得数据但不从ADC 2获取数据。我应该能够通过将选择引脚拉低来选择ADC 2,但我得到的只有0.有16个光电二极管连接到4 TLC2274运算放大器。这是Arduino代码:

//Scott Little, BrainGoggles, 2013, GNU GPL v3
#include <SoftwareSerial.h>
#include "Tlc5940.h"
SoftwareSerial bluetooth(4,2);  //TX 4, RX 2

#define SELPIN 7 //Selection Pin for 1st ADC
#define SELPIN2 8 //Selection Pin for 2nd ADC
#define DATAOUT 12//MOSI 
#define DATAIN  5//MISO 
#define SPICLOCK  6//Clock 
int readvalue;
byte readvaluearray[32];
int intensity = 0;

void setup()
{
  /* Call Tlc.init() to setup the tlc.
     You can optionally pass an initial PWM value (0 - 4095) for all channels.*/
  Tlc.init();  //interferes with other SPI
  Tlc.clear();  //set pin modes 

  pinMode(SELPIN, OUTPUT); //adc 1 selection pin
  pinMode(SELPIN2, OUTPUT); //adc 2 selection pin
  pinMode(DATAOUT, OUTPUT); 
  pinMode(DATAIN, INPUT); 
  pinMode(SPICLOCK, OUTPUT); 
  //disable devices to start with 
  digitalWrite(SELPIN,HIGH); 
  digitalWrite(SELPIN2,HIGH);
  digitalWrite(DATAOUT,LOW); 
  digitalWrite(SPICLOCK,LOW); 
  bluetooth.begin(9600); 
  Serial.begin(9600);

}

void loop()
{
  if (bluetooth.available()) // Wait until a character is received
  {
    char val = (char)bluetooth.read();
    Serial.println(val);

    switch(val) // Perform an action depending on the command
    {
      case 't'://increase intensity when an 'e' is received
    intensity = plus(intensity);
      break;      

      case 'y'://decrease intensity when an 'r' is received
    intensity = minus(intensity);
      break;

      case 'q'://turn the light on when a 'q' is received
    on();
      break;

      case 'w'://turn the light off when a 'w' is received
    off();
      break;
    }
  }

  for (int i=0; i<8; i++){        //read from ADC 1
    readvalue = read_adc(i+1);
    readvaluearray[2*i] = highByte(readvalue);
    readvaluearray[2*i+1] = lowByte(readvalue);
  }

  for (int i=8; i<16; i++){        //read from ADC 2
    readvalue = read_adc2(i-7);
    readvaluearray[2*i] = highByte(readvalue);
    readvaluearray[2*i+1] = lowByte(readvalue);
  }

  bluetooth.write(readvaluearray,32);
  Serial.println("new");
  for (int i=0;i<16;i++){
    Serial.println(word(readvaluearray[2*i],readvaluearray[2*i+1]));
  }

  delay(2000);
}


int read_adc(int channel){
  int adcvalue = 0;
  byte commandbits = B11000000; //command bits - start, mode, chn (3), dont care (3)

  //allow channel selection
  commandbits|=((channel-1)<<3);

  digitalWrite(SELPIN,LOW); //Select adc

  // setup bits to be written
  for (int i=7; i>=3; i--){
    digitalWrite(DATAOUT,commandbits&1<<i);
    //cycle clock
    digitalWrite(SPICLOCK,HIGH);
    digitalWrite(SPICLOCK,LOW);    
  }

  digitalWrite(SPICLOCK,HIGH);    //ignores 2 null bits
  digitalWrite(SPICLOCK,LOW);
  digitalWrite(SPICLOCK,HIGH);  
  digitalWrite(SPICLOCK,LOW);

  //read bits from adc
  for (int i=11; i>=0; i--){
    adcvalue+=digitalRead(DATAIN)<<i;
    //cycle clock
    digitalWrite(SPICLOCK,HIGH);
    digitalWrite(SPICLOCK,LOW);
  }
  digitalWrite(SELPIN, HIGH); //turn off device

  return adcvalue;
}

int read_adc2(int channel){
  int adcvalue = 0;
  byte commandbits = B11000000; //command bits - start, mode, chn (3), dont care (3)

  //allow channel selection
  commandbits|=((channel-1)<<3);

  digitalWrite(SELPIN2,LOW); //Select adc

  // setup bits to be written
  for (int i=7; i>=3; i--){
    digitalWrite(DATAOUT,commandbits&1<<i);
    //cycle clock
    digitalWrite(SPICLOCK,HIGH);
    digitalWrite(SPICLOCK,LOW);    
  }

  digitalWrite(SPICLOCK,HIGH);    //ignores 2 null bits
  digitalWrite(SPICLOCK,LOW);
  digitalWrite(SPICLOCK,HIGH);  
  digitalWrite(SPICLOCK,LOW);

  //read bits from adc
  for (int i=11; i>=0; i--){
    adcvalue+=digitalRead(DATAIN)<<i;
    //cycle clock
    digitalWrite(SPICLOCK,HIGH);
    digitalWrite(SPICLOCK,LOW);
  }
  digitalWrite(SELPIN2, HIGH); //turn off device

  return adcvalue;
}

void on(void)
{
  Tlc.set(1, 4095);  //set pin 5 to max brightness
  Tlc.update();  //execute set
  //bluetooth.println("on");
  //Serial.println("on");
}

void off(void)
{
  Tlc.set(1, 0);  //set pin 5 to min brightness
  Tlc.update();  //execute set
  //bluetooth.println("off");
  //Serial.println("off");
}

int plus(int value)
{
  value = value + 64;
  if (value > 4095){value = 4095;}
  Tlc.set(1, value);  //set pin 5 to min brightness
  Tlc.update();  //execute set
  Serial.println(value);
  return value;
}

int minus(int value)
{
  value = value - 64;
  if (value < 0){value = 0;}
  Tlc.set(1, value);  //set pin 5 to min brightness
  Tlc.update();  //execute set
  Serial.println(value);
  return value;
}

以下是我得到的示例输出:

new
374
372
311
313
356
276
337
387
0
0
0
0
0
0
0
0

2 个答案:

答案 0 :(得分:1)

我设计了一个草图,用于在我的Arduino uno上使用TLC5940驱动10个(或更多)RGB LED。这也可能适用于纳米。我在30个通道上驱动10个共阳极rgb LED,两个TLC5940的菊花链在一起。只要您配置了多少个TLC5940芯片,我们就可以实现更多目标。这适用于12位占空比控制(0 - 4095)。

  1. 在arduino IDE中,您必须从Paul Stoffregen导入TLC5940库:https://github.com/PaulStoffregen/Tlc5940

  2. 编辑tlc_config.h文件,其中NUM_TLC应该等于2(默认为1):

    “#define NUM_TLCS 2”

  3. 现在我们可以看一下草图来运行

  4. 这是草图的布线: enter image description here

    虽然这描绘了单色LED,但我将映射我的rgb引脚0-2,3-5,6-8,9-11 ......等等。

    CODE:

    #include "Tlc5940.h"
    
    int rgbChannels = 30;//total channels used one the TLC5940's
    int rgb[30]; ///should be the same as the number of channels
    int rgbLights = 10;/// this is the number of rgb leds possible on 2 TLC5940's but you could always daisy chain more...
    int colorArray[10];//this sets the number of colors to use (one per rgb led)
    
    void setup() {
      // put your setup code here, to run once
      Tlc.init(0); // Initiates the TLC5940 and set all channels off
      Serial.begin(250000);
      Serial.println("Total Channels: " + String(rgbChannels) + "  Total
    RGB Ligts: " + String(rgbLights));
      float divisor = 360 / (rgbChannels / 3); //degrees of color to
    display divided by the number of rgb lights
      Serial.println("Divisor: " + String(divisor) );
      float Step = divisor;
      for (int i = 0; i < rgbLights; i++) {
        colorArray[i] = Step;
        Serial.println("colorArray[" + String(i) + "]: " + String(colorArray[i]));
        Step = Step + divisor;
      }
    }
    
    void ledColor(int channel, int red, int green, int blue)
    {
      Tlc.set(channel, red);
      Tlc.set(channel + 1, green);
      Tlc.set(channel + 2, blue);
    }
    
    ///convert hsi color to rgb
    void hsi_to_rgb(int startChannel, float H, float S, float I) {
      int r, g, b;
      if (H > 360) {
        H = H - 360;
      }
      // Serial.println("H: "+String(H));
      H = fmod(H, 360); // cycle H around to 0-360 degrees
      H = 3.14159 * H / (float)180; // Convert to radians.
      S = S > 0 ? (S < 1 ? S : 1) : 0; // clamp S and I to interval [0,1]
      I = I > 0 ? (I < 1 ? I : 1) : 0;
      if (H < 2.09439) {
        r = 4095 * I / 3 * (1 + S * cos(H) / cos(1.047196667 - H));
        g = 4095 * I / 3 * (1 + S * (1 - cos(H) / cos(1.047196667 - H)));
        b = 4095 * I / 3 * (1 - S);
      } else if (H < 4.188787) {
        H = H - 2.09439;
        g = 4095 * I / 3 * (1 + S * cos(H) / cos(1.047196667 - H));
        b = 4095 * I / 3 * (1 + S * (1 - cos(H) / cos(1.047196667 - H)));
        r = 4095 * I / 3 * (1 - S);
      } else {
        H = H - 4.188787;
        b = 4095 * I / 3 * (1 + S * cos(H) / cos(1.047196667 - H));
        r = 4095 * I / 3 * (1 + S * (1 - cos(H) / cos(1.047196667 - H)));
        g = 4095 * I / 3 * (1 - S);
      }
      rgb[0 + startChannel] = r;
      rgb[1 + startChannel] = g;
      rgb[2 + startChannel] = b;
    
    }
    
    
    void rainbowShift() {
      float brightness = .4;
      float saturation = 1;
      for (int n = 0; n <= 360; n++) {
        for (int i = 0, j = 0; i < rgbLights; i++) {
          hsi_to_rgb(j, colorArray[i] + n, saturation, brightness);
          //Serial.println("rgb"+String(i)+":"+String(rgb[j])+","+String(rgb[j+1])+","+String(rgb[j+2]));
          ledColor(j, rgb[j], rgb[j + 1], rgb[j + 2]);
          j = j + 3;
        }
        Tlc.update();
        Tlc.clear();
        delayMicroseconds(500);
      }
    }
    
    
    
    void loop() {
      // put your main code here, to run repeatedly:
    rainbowShift();////perform the function a few times
    
    }
    

    当一切都完成后,您应该在RGB LED上移动彩虹色

    观看此视频:

    <iframe width="560" height="315" src="https://www.youtube.com/embed/CWdL9i8U8U0" frameborder="0" allowfullscreen></iframe>

    以下是结果图: enter image description here

答案 1 :(得分:0)

现在正在运作。我将对应于DOUT(ADC 12)的ADC上的引脚物理地更改为与MISO(Arduino 12)对应的Arduino上的引脚,并更改了代码:

#define DATAOUT 5  //MOSI 
#define DATAIN  12 //MISO 

它应该像以前一样工作,因为我有点敲打,但现在似乎工作,因为MISO在“正确”的引脚上。