View source for Lesson 27--Microduino 8*8 Lattice Static Display

{{Language|第二十七课--Microduino 8*8点阵静态显示}}
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==Objective==
The tutorial will teach you use two 74HC595 to control 8** lattice and display a static smiling faces.
==Equipment==
*'''[[Microduino-Core]]'''
*'''[[Microduino-FT232R]]'''
*Other hardware equipment
**Breadboard Jumper            one box   
**Breadboard  	               one piece  
**8*8 lattice                  one
**74HC595                      Two
**USB cable                    one


'''8*8 lattice LED introduction：'''
8*8 lattice LED is made of 64 light-emitting diodes, differenet type has different definition of the pin. This example uses the LD-1088BS 8*8 lattice LED, the pins are defined as follows:
[[File:第二十七课-Microduino 8_8点阵引脚定义.jpg|600px|center|thumb]]

==Schematice==
[[File:第二十七课-Microduino 8_8点阵静态显示原理图.jpg|600px|center|thumb]]


Pin Table：
{| class="wikitable"
|-
! Lattice ROW !! Lattice 16pin !! 74HC595 !! 74HC595
|-
| 1 || 13 || 15 || Q0
|-
| 2 || 3 || 1 || Q1
|-
| 3 || 4 || 2 || Q2
|-
| 4 || 10 || 3 || Q3
|-
| 5 || 6 || 4 || Q4
|-
| 6 || 11 || 5 || Q5
|-
| 7 || 15 || 6 || Q6
|-
| 8 || 16 || 7 || Q7
|}

{| class="wikitable"
|-
! Lattice COL !! Lattice 16pin !! 74HC595 !! 74HC595
|-
| 1 || 5 || 15 || Q0
|-
| 2 || 2 || 1 || Q1
|-
| 3 || 7 || 2 || Q2
|-
| 4 || 1 || 3 || Q3
|-
| 5 || 12 || 4 || Q4
|-
| 6 || 8 || 5 || Q5
|-
| 7 || 14 || 6 || Q6
|-
| 8 || 9 || 7 || Q7
|}

==Program==
<source lang="cpp">


    //Pin connects to 74HC595的ST_CP
    int latchPin = 8;
    //Pin connects to 74HC595的SH_CP
    int clockPin = 12;
    ////Pin connects to 74HC595的DS
    int dataPin = 11;
     
     
     
    void setup() {
      //Set barud roate 9600   
      Serial.begin(9600);
      //Set the latchpin as output
      pinMode(latchPin, OUTPUT);
     
    }
     
    void loop() {
      //Smile for 8x8 Matrix LED
      digitalWrite(latchPin, 0);
      shiftOut(dataPin, clockPin, B01111111);  //col
      shiftOut(dataPin, clockPin, B00111100);  //row
      digitalWrite(latchPin, 1);
     
      digitalWrite(latchPin, 0);
      shiftOut(dataPin, clockPin, B10111111);  //col
      shiftOut(dataPin, clockPin, B01000010);  //row
      digitalWrite(latchPin, 1);
     
      digitalWrite(latchPin, 0);
      shiftOut(dataPin, clockPin, B11011111);  //col
      shiftOut(dataPin, clockPin, B10100101);  //row
      digitalWrite(latchPin, 1);
     
      digitalWrite(latchPin, 0);
      shiftOut(dataPin, clockPin, B11101111);  //col
      shiftOut(dataPin, clockPin, B10000001);  //row
      digitalWrite(latchPin, 1);
     
      digitalWrite(latchPin, 0);
      shiftOut(dataPin, clockPin, B11110111);  //col
      shiftOut(dataPin, clockPin, B10100101);  //row
      digitalWrite(latchPin, 1);
     
      digitalWrite(latchPin, 0);
      shiftOut(dataPin, clockPin, B11111011);  //col
      shiftOut(dataPin, clockPin, B10011001);  //row
      digitalWrite(latchPin, 1);
     
      digitalWrite(latchPin, 0);
      shiftOut(dataPin, clockPin, B11111101);  //col)
      shiftOut(dataPin, clockPin, B01000010);  //row
      digitalWrite(latchPin, 1);
     
      digitalWrite(latchPin, 0);
      shiftOut(dataPin, clockPin, B11111110);  //col
      shiftOut(dataPin, clockPin, B00111100);  //row
      digitalWrite(latchPin, 1);
     
     
    }
     
    void shiftOut(int myDataPin, int myClockPin, byte myDataOut) {
     
      //initialization
      int i=0;
      int pinState;
      pinMode(myClockPin, OUTPUT);
      pinMode(myDataPin, OUTPUT);
     
      //clear everything out just in case to
      //prepare shift register for bit shifting
      digitalWrite(myDataPin, 0);
      digitalWrite(myClockPin, 0);
     
      //for each bit in the byte myDataOut&#239;&#191;&#189;
      //NOTICE THAT WE ARE COUNTING DOWN in our for loop
      //This means that %00000001 or "1" will go through such
      //that it will be pin Q0 that lights.
      for (i=7; i>=0; i--)  {
        digitalWrite(myClockPin, 0);
     
        //if the value passed to myDataOut and a bitmask result
        // true then... so if we are at i=6 and our value is
        // %11010100 it would the code compares it to %01000000
        // and proceeds to set pinState to 1.
        if ( myDataOut & (1<<i) ) {
          pinState= 1;
        }
        else {       
          pinState= 0;
        }
     
        //Sets the pin to HIGH or LOW depending on pinState
        digitalWrite(myDataPin, pinState);
        //register shifts bits on upstroke of clock pin  
        digitalWrite(myClockPin, 1);
        //zero the data pin after shift to prevent bleed through
        digitalWrite(myDataPin, 0);
      }
     
      //stop shifting
      digitalWrite(myClockPin, 0);
    }


</source>

==Debug==
Step 1：Copy the code to IDE and compile it

Step 2：Set up circuit, as follows:
[[File:第二十七课-Microduino 8_8点阵静态显示连接图.jpg|600px|center|thumb]]
In order to protect the circuit, plus a 220Ω registor on the every connection line (total 8 lines) between one 74HC595 chip and 8*8 latteice LED. In our example, we don't use the registor, so the LED's brightnees is strong. If  the lattice's quality is bad and easily broken. 

Step 3：Run program

==Result==

8*8 lattice LED will diaplya a smiling face.

==Video==