Difference between revisions of "Adafruit: 8x8 Red LED Matrix Panel"

From eLinux.org
Jump to: navigation, search
(Wire Connection)
m (Overview: Added Grade)
 
(20 intermediate revisions by 2 users not shown)
Line 1: Line 1:
[[Category:ECE497]][[Category:Adafruit]]
+
[[Category:ECE497]]
 +
[[Category:Adafruit]]
 +
 
 +
== Overview ==
 +
<pre style="color:red">
 +
Overview: 2
 +
Wiring:  1, Include the header number
 +
Code:    1, Clean it up some more.
 +
git/Compiles with make: 2  make works
 +
Demo:    2
 +
Total:    8 
 +
Comments: Looks good. The cod has lots of extra things that aren't needed.
 +
The video is a nice touch.
 +
</pre>
  
 
== Overview ==
 
== Overview ==
Line 5: Line 18:
 
My mini project 2 is using an Adafriut 8*8 red LED matrix to show 2 animations. First animation is to composite a diamond and then fade out. The second animation is to drop down a horizontal bar to the bottom of the LED matrix until all the lines are being filled. When the two animations were done, the LED matrix will flash 5 times and shut down.  
 
My mini project 2 is using an Adafriut 8*8 red LED matrix to show 2 animations. First animation is to composite a diamond and then fade out. The second animation is to drop down a horizontal bar to the bottom of the LED matrix until all the lines are being filled. When the two animations were done, the LED matrix will flash 5 times and shut down.  
  
The code that being used in this project is modified from the sample code provided by Dr. Mark A. Yoder. The new version of the code that contained my animation has been commited to my github which you can find at here: [https://github.com/1984xiali/lix_beaglebone Mini-project 2 by Xia Li].
+
The code that being used in this project is modified from the sample code provided by Dr. Mark A. Yoder. The new version of the code that contained my animation has been commited to my github which you can find at here: [https://github.com/1984xiali/ECE497_mini_project2 Mini-project 2 by Xia Li].
  
 
== Wire Connection ==
 
== Wire Connection ==
  
The wire connection part is not very complex. As you can see in the picture, Pin3 VDD3.3v and pin45 connect to breadboard's positive and negative line which are red and blue. Pin19 and pin20 are i2c2_SCL and i2c2_SDA which will be connected to LED matrix's c pin and d pin. '''Don't forget the two 4.3KΩ pull-up resistors.'''
+
The wire connection part is not very complex. As you can see in the picture
 +
<span style="color:red">Which header are you using?  It looks like P9</span>
 +
 
 +
pin3 VDD3.3v   ----> breadboard's positive(red line)
 +
 
 +
pin45 GND      ----> breadboard's negative(blue line)
 +
 
 +
pin19 i2c2_SCL ----> LED matrix's c pin
 +
 
 +
pin20 i2c2_SDA ----> LED matrix's d pin.  
 +
 
 +
'''Don't forget the two 4.3KΩ pull-up resistors.'''
 +
 
 +
LED matrix's + - pin ----> breadboard's positive and negative
  
 
The wire connection picture:
 
The wire connection picture:
  
[[File:wire connection.JPG|500px]]
+
[[File:Wire connection.jpg|500px]]
 +
 
 +
Here is a hand by hand tutorial about I2C wrote by Dr. Yoder. If you need that [http://www.elinux.org/EBC_Exercise_12_I2C Click here].
  
 
== Software Design ==
 
== Software Design ==
  
After I went through the sample code. I found several points very important and you need to understand:
+
=== Important facts===
 +
 
 +
After I went through the sample code. I found several points which are very important. You may need to understand before you move on:
  
 
1. i2cbus is 3
 
1. i2cbus is 3
Line 30: Line 60:
  
 
6. array smile_bmp[], frown_bmp[], and neutral_bmp[] are save the hex-decimal value for each line on LED matrix
 
6. array smile_bmp[], frown_bmp[], and neutral_bmp[] are save the hex-decimal value for each line on LED matrix
 +
 +
=== Theory===
  
 
The theory is when you convert the hex-decimal value of each line to binary value, you will get a 8 bit binary number for each line. Each bit will stand for each led point on the corresponding line. 0 for off, 1 for on.
 
The theory is when you convert the hex-decimal value of each line to binary value, you will get a 8 bit binary number for each line. Each bit will stand for each led point on the corresponding line. 0 for off, 1 for on.
  
For example: 0x18 = 1 * 16 + 8 = 24(decimal) = 0 0 0 1 1 0 0 0(binary)
+
For example: 0x18 = 1 * 16 + 8 = 24(decimal) = <span style="color:red">0 0 0 1 1 0 0 0(binary)</span>
  
This value means the 4th and 5th led position will be on, all the others will be off on that line.
+
This value means the 4th and 5th led position of that line will be on, all the other leds will be off.
After you understand this, you can program your pattern or animation.
+
As long as you understand this, you can program your own patterns or animations.
  
I create 4 patterns for diamond animation:
+
=== My Animations Analysis===
  
pic1_bmp[]={0x18, 0x3C, 0x7E, 0xFF, 0xFF, 0x7E, 0x3C, 0x18}
+
I create 4 patterns for diamond animation:
 
+
pic2_bmp[]={0x18, 0x3C, 0x7E, 0xE7, 0xE7, 0x7E, 0x3C, 0x18}
+
  
pic3_bmp[]={0x18, 0x3C, 0x66, 0xC3, 0xC3, 0x66, 0x3C, 0x18}
+
pic1_bmp[]={0x18, 0x3C, 0x7E, 0xFF, 0xFF, 0x7E, 0x3C, 0x18}
 +
pic2_bmp[]={0x18, 0x3C, 0x7E, 0xE7, 0xE7, 0x7E, 0x3C, 0x18}
 +
pic3_bmp[]={0x18, 0x3C, 0x66, 0xC3, 0xC3, 0x66, 0x3C, 0x18}
 +
pic4_bmp[]={0x18, 0x24, 0x42, 0x81, 0x81, 0x42, 0x24, 0x18}
  
pic4_bmp[]={0x18, 0x24, 0x42, 0x81, 0x81, 0x42, 0x24, 0x18}
+
The horizontal bar animation only need 1 pattern:
  
The horizontal bar only need 1 pattern:
+
line_bmp[]={0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}
  
line_bmp[]={0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}
+
=== Source Code===
  
Below is the major part of the code:
+
Below is the major part of the source code:
  
 
<pre>
 
<pre>
Line 134: Line 167:
 
while(q>=0){
 
while(q>=0){
 
j=0;
 
j=0;
while(j<=q){
+
while(j<=q){   //nested loop to make it work
 
for(i=0; i<8; i++){
 
for(i=0; i<8; i++){
 
block[i] = (line_bmp[i]&0xfe) >> 1 |
 
block[i] = (line_bmp[i]&0xfe) >> 1 |
Line 166: Line 199:
 
</pre>
 
</pre>
  
The source code can be download from my github at: [https://github.com/1984xiali/lix_beaglebone Mini-project 2 by Xia Li].
+
The source code can be download from my github at: [https://github.com/1984xiali/ECE497_mini_project2 Mini-project 2 by Xia Li].
  
 
== Demo of Animation==
 
== Demo of Animation==
  
I uploaded a video demo of my animation to www.youtube.com. The link is: [http://www.youtube.com/watch?v=sZkMx70ZvbI Demo link].
+
I uploaded a video demo of my animation to www.youtube.com.  
 +
 
 +
=== Adafruit: 8*8 Red LED Matrix ===
 +
{{#ev:youtube|sZkMx70ZvbI}}
 +
 
 +
The link is: [http://www.youtube.com/watch?v=sZkMx70ZvbI http://www.youtube.com/watch?v=sZkMx70ZvbI].
 +
Enjoy it and have fun!
 +
 
 +
Xia Li

Latest revision as of 18:50, 14 November 2012


Overview

Overview: 2
Wiring:   1, Include the header number
Code:     1, Clean it up some more.
git/Compiles with make: 2  make works
Demo:     2
Total:    8  
Comments: Looks good. The cod has lots of extra things that aren't needed.
The video is a nice touch.

Overview

My mini project 2 is using an Adafriut 8*8 red LED matrix to show 2 animations. First animation is to composite a diamond and then fade out. The second animation is to drop down a horizontal bar to the bottom of the LED matrix until all the lines are being filled. When the two animations were done, the LED matrix will flash 5 times and shut down.

The code that being used in this project is modified from the sample code provided by Dr. Mark A. Yoder. The new version of the code that contained my animation has been commited to my github which you can find at here: Mini-project 2 by Xia Li.

Wire Connection

The wire connection part is not very complex. As you can see in the picture Which header are you using? It looks like P9

pin3 VDD3.3v ----> breadboard's positive(red line)

pin45 GND ----> breadboard's negative(blue line)

pin19 i2c2_SCL ----> LED matrix's c pin

pin20 i2c2_SDA ----> LED matrix's d pin.

Don't forget the two 4.3KΩ pull-up resistors.

LED matrix's + - pin ----> breadboard's positive and negative

The wire connection picture:

Wire connection.jpg

Here is a hand by hand tutorial about I2C wrote by Dr. Yoder. If you need that Click here.

Software Design

Important facts

After I went through the sample code. I found several points which are very important. You may need to understand before you move on:

1. i2cbus is 3

2. i2c address is 0x70

3. oscillator daddress is 0x21

4. display on daddress is 0x81

5. Full brightness is 0xE7

6. array smile_bmp[], frown_bmp[], and neutral_bmp[] are save the hex-decimal value for each line on LED matrix

Theory

The theory is when you convert the hex-decimal value of each line to binary value, you will get a 8 bit binary number for each line. Each bit will stand for each led point on the corresponding line. 0 for off, 1 for on.

For example: 0x18 = 1 * 16 + 8 = 24(decimal) = 0 0 0 1 1 0 0 0(binary)

This value means the 4th and 5th led position of that line will be on, all the other leds will be off. As long as you understand this, you can program your own patterns or animations.

My Animations Analysis

I create 4 patterns for diamond animation:

pic1_bmp[]={0x18, 0x3C, 0x7E, 0xFF, 0xFF, 0x7E, 0x3C, 0x18}
pic2_bmp[]={0x18, 0x3C, 0x7E, 0xE7, 0xE7, 0x7E, 0x3C, 0x18}
pic3_bmp[]={0x18, 0x3C, 0x66, 0xC3, 0xC3, 0x66, 0x3C, 0x18}
pic4_bmp[]={0x18, 0x24, 0x42, 0x81, 0x81, 0x42, 0x24, 0x18}

The horizontal bar animation only need 1 pattern:

line_bmp[]={0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}

Source Code

Below is the major part of the source code:


static __u16 smile_bmp[]={0x3C, 0x42, 0x95, 0xA1, 0xA1, 0x95, 0x42, 0x3C};
static __u16 test_bmp[]={0x3C, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF};
static __u16 frown_bmp[]={0x3C, 0x42, 0xA5, 0x91, 0x91, 0xA5, 0x42, 0x3C};
static __u16 neutral_bmp[]={0x3C, 0x42, 0x95, 0x91, 0x91, 0x95, 0x42, 0x3C};
static __u16 pic1_bmp[]={0x18, 0x3C, 0x7E, 0xFF, 0xFF, 0x7E, 0x3C, 0x18};
static __u16 pic2_bmp[]={0x18, 0x3C, 0x7E, 0xE7, 0xE7, 0x7E, 0x3C, 0x18};
static __u16 pic3_bmp[]={0x18, 0x3C, 0x66, 0xC3, 0xC3, 0x66, 0x3C, 0x18};
static __u16 pic4_bmp[]={0x18, 0x24, 0x42, 0x81, 0x81, 0x42, 0x24, 0x18};

static __u16 line_bmp[]={0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};

// Demo 1 is showing...
printf("Demo 1 is showing...\n");
while(counter <= 1)
{
for(i=0; i<8; i++){
block[i] = (pic1_bmp[i]&0xfe) >> 1 |
(pic1_bmp[i]&0x01) << 7;
}
res = i2c_smbus_write_i2c_block_data(file, daddress, 16,
(__u8 *)block);

usleep(500000);
for(i=0; i<8; i++){
block[i] = (pic2_bmp[i]&0xfe) >> 1 |
(pic2_bmp[i]&0x01) << 7;
}
res = i2c_smbus_write_i2c_block_data(file, daddress, 16,
(__u8 *)block);

usleep(500000);
for(i=0; i<8; i++){
block[i] = (pic3_bmp[i]&0xfe) >> 1 |
(pic3_bmp[i]&0x01) << 7;
}
res = i2c_smbus_write_i2c_block_data(file, daddress, 16,
(__u8 *)block);

usleep(500000);
for(i=0; i<8; i++){
block[i] = (pic4_bmp[i]&0xfe) >> 1 |
(pic4_bmp[i]&0x01) << 7;
}
res = i2c_smbus_write_i2c_block_data(file, daddress, 16,
(__u8 *)block);

usleep(500000);
for(i=0; i<8; i++){
block[i] = (pic3_bmp[i]&0xfe) >> 1 |
(pic3_bmp[i]&0x01) << 7;
}
res = i2c_smbus_write_i2c_block_data(file, daddress, 16,
(__u8 *)block);

usleep(500000);
for(i=0; i<8; i++){
block[i] = (pic2_bmp[i]&0xfe) >> 1 |
(pic2_bmp[i]&0x01) << 7;
}
res = i2c_smbus_write_i2c_block_data(file, daddress, 16,
(__u8 *)block);

usleep(500000);
for(i=0; i<8; i++){
block[i] = (pic1_bmp[i]&0xfe) >> 1 |
(pic1_bmp[i]&0x01) << 7;
}
res = i2c_smbus_write_i2c_block_data(file, daddress, 16,
(__u8 *)block);

usleep(500000);

counter += 1;
}
// Demo 2 is showing...
printf("Demo 2 is showing...\n");
while(q>=0){
j=0;
while(j<=q){    //nested loop to make it work
for(i=0; i<8; i++){
block[i] = (line_bmp[i]&0xfe) >> 1 |
(line_bmp[i]&0x01) << 7;
}
res = i2c_smbus_write_i2c_block_data(file, daddress, 16,
(__u8 *)block);

usleep(500000);
if(j<q){
tmp = line_bmp[j];
line_bmp[j] = line_bmp[j+1];
line_bmp[j+1] = tmp;
}
if(j==q){
line_bmp[0] = 0xFF;
}
j++;
}
q--;
}

daddress = 0x83;// Display off, blinking on
printf("writing: 0x%02x\n", daddress);
res = i2c_smbus_write_byte(file, daddress);

usleep(3000000);
daddress = 0x80;// Display off
printf("writing: 0x%02x\n", daddress);
res = i2c_smbus_write_byte(file, daddress);

The source code can be download from my github at: Mini-project 2 by Xia Li.

Demo of Animation

I uploaded a video demo of my animation to www.youtube.com.

Adafruit: 8*8 Red LED Matrix

The link is: http://www.youtube.com/watch?v=sZkMx70ZvbI. Enjoy it and have fun!

Xia Li