SunFounder RGB Matrix Module for Raspberry Pi¶
Welcome to use SunFounder RGB Matrix module. You can find the information you need for use here.
This is a module with 8 × 8 RGB LEDs on board. It also has a SH1.0-4P I2C control interface, which is convenient to connect to other I2C devices or other single-chip microcomputers.
Here is the Email: cs@sunfounder.com.
Features¶
Working voltage: DC 3.3V
Lamp bead: FM-N3535RGBW-SH
Driver: SLED 1734X LED driver
Communication method: I2C
Color depth: 24 bit (R/G/B each 8 bit color, 256 x 256 x 256=16777216 colors can be combined)
Resolution: 8*8=64 DOTS
Pixel pitch: 4.7mm
matrix size: 36.5mm*36.5mm
Documentation
Assemble RGB Matrix HAT¶
Preparation¶
In this chapter, we firstly learn to start up Raspberry Pi. The content includes installing the OS, Raspberry Pi network and how to open terminal.
Note
You can check the complete tutorial on the official website of the Raspberry Pi: raspberry-pi-setting-up.
If your Raspberry Pi is set up, you can skip the part and go into the next chapter.
What Do We Need?¶
Required Components¶
Raspberry Pi
The Raspberry Pi is a low cost, credit-card sized computer that plugs into a computer monitor or TV, and uses a standard keyboard and mouse. It is a capable little device that enables people of all ages to explore computing, and to learn how to program in languages like Scratch and Python.
Our kit applies to the following versions of the product of Raspberry Pi
Power Adapter
To connect to a power socket, the Raspberry Pi has a micro USB port (the same found on many mobile phones). You will need a power supply which provides at least 2.5 amps.
Micro SD Card
Your Raspberry Pi needs an Micro SD card to store all its files and the Raspberry Pi OS. You will need a micro SD card with a capacity of at least 8 GB
Optional Components¶
Screen
To view the desktop environment of Raspberry Pi, you need to use the screen that can be a TV screen or a computer monitor. If the screen has built-in speakers, the Pi plays sounds via them.
Mouse & Keyboard
When you use a screen , a USB keyboard and a USB mouse are also needed.
HDMI
The Raspberry Pi has a HDMI output port that is compatible with the HDMI ports of most modern TV and computer monitors. If your screen has only DVI or VGA ports, you will need to use the appropriate conversion line.
Case
You can put the Raspberry Pi in a case; by this means, you can protect your device.
Sound or Earphone
The Raspberry Pi is equipped with an audio port about 3.5 mm that can be used when your screen has no built-in speakers or when there is no screen operation.
Installing the OS¶
Required Components
Any Raspberry Pi |
1 * Personal Computer |
1 * Micro SD card |
Step 1
Raspberry Pi have developed a graphical SD card writing tool that works on Mac OS, Ubuntu 18.04 and Windows, and is the easiest option for most users as it will download the image and install it automatically to the SD card.
Visit the download page: https://www.raspberrypi.org/software/. Click on the link for the Raspberry Pi Imager that matches your operating system, when the download finishes, click it to launch the installer.
Step 2
When you launch the installer, your operating system may try to block you from running it. For example, on Windows I receive the following message:
If this pops up, click on More info and then Run anyway, then follow the instructions to install the Raspberry Pi Imager.
Step 3
Insert your SD card into the computer or laptop SD card slot.
Step 4
In the Raspberry Pi Imager, select the OS that you want to install and the SD card you would like to install it on.
Note
You will need to be connected to the internet the first time.
That OS will then be stored for future offline use(lastdownload.cache, C:/Users/yourname/AppData/Local/Raspberry Pi/Imager/cache). So the next time you open the software, it will have the display “Released: date, cached on your computer”.
Step 5
Select the SD card you are using.
Step 6
Press Ctrl+Shift+X to open the Advanced options page to enable SSH and configure wifi, these 2 items must be set, the others depend on your choice . You can choose to always use this image customization options.
Then scroll down to complete the wifi configuration and click SAVE.
Note
wifi country should be set the two-letter ISO/IEC alpha2 code for the country in which you are using your Raspberry Pi, please refer to the following link: https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2#Officially_assigned_code_elements
Step 7
Click the WRITE button.
Step 8
If your SD card currently has any files on it, you may wish to back up these files first to prevent you from permanently losing them. If there is no file to be backed up, click Yes.
Step 9
After waiting for a period of time, the following window will appear to represent the completion of writing.
Set up Your Raspberry Pi¶
If You Have a Screen¶
If you have a screen, it will be easy for you to operate on the Raspberry Pi.
Required Components
Any Raspberry Pi |
1 * Power Adapter |
1 * Micro SD card |
1 * Screen Power Adapter |
1 * HDMI cable |
1 * Screen |
1 * Mouse |
1 * Keyboard |
Insert the SD card you’ve set up with Raspberry Pi OS into the micro SD card slot on the underside of your Raspberry Pi.
Plug in the Mouse and Keyboard.
Connect the screen to Raspberry Pi’s HDMI port and make sure your screen is plugged into a wall socket and switched on.
Note
If you use a Raspberry Pi 4, you need to connect the screen to the HDMI0 (nearest the power in port).
Use the power adapter to power the Raspberry Pi. After a few seconds, the Raspberry Pi OS desktop will be displayed.
If You Have No Screen¶
If you don’t have a display, you can log in to the Raspberry Pi remotely, but before that, you need to get the IP of the Raspberry Pi.
Get the IP Address¶
After the Raspberry Pi is connected to WIFI, we need to get the IP address of it. There are many ways to know the IP address, and two of them are listed as follows.
1. Checking via the router
If you have permission to log in the router(such as a home network), you can check the addresses assigned to Raspberry Pi on the admin interface of router.
The default hostname of the Raspberry Pi OS is raspberrypi, and you need to find it. (If you are using ArchLinuxARM system, please find alarmpi.)
2. Network Segment Scanning
You can also use network scanning to look up the IP address of Raspberry Pi. You can apply the software, Advanced IP scanner and so on.
Scan the IP range set, and the name of all connected devices will be displayed. Similarly, the default hostname of the Raspberry Pi OS is raspberrypi, if you haven’t modified it.
Use the SSH Remote Control¶
We can open the Bash Shell of Raspberry Pi by applying SSH. Bash is the standard default shell of Linux. The Shell itself is a program written in C that is the bridge linking the customers and Unix/Linux. Moreover, it can help to complete most of the work needed.
For Linux or/Mac OS X Users
Step 1
Go to Applications->Utilities, find the Terminal, and open it.
Step 2
Type in ssh pi@ip_address . “pi”is your username and “ip_address” is your IP address. For example:
ssh pi@192.168.18.197
Step 3
Input”yes”.
Step 4
Input the passcode and the default password is raspberry.
Step 5
We now get the Raspberry Pi connected and are ready to go to the next step.
Note
When you input the password, the characters do not display on window accordingly, which is normal. What you need is to input the correct password.
For Windows Users
If you’re a Windows user, you can use SSH with the application of some software. Here, we recommend PuTTY.
Step 1
Download PuTTY.
Step 2
Open PuTTY and click Session on the left tree-alike structure. Enter the IP address of the RPi in the text box under Host Name (or IP address) and 22 under Port (by default it is 22).
Step 3
Click Open. Note that when you first log in to the Raspberry Pi with the IP address, there prompts a security reminder. Just click Yes.
Step 4
When the PuTTY window prompts “login as:”, type in “pi”(the user name of the RPi), and password: “raspberry” (the default one, if you haven’t changed it).
Note
When you input the password, the characters do not display on window accordingly, which is normal. What you need is to input the correct password.
If inactive appears next to PuTTY, it means that the connection has been broken and needs to be reconnected.
Step 5
Here, we get the Raspberry Pi connected and it is time to conduct the next steps.
Note
If you are not satisfied with using the command window to control the Raspberry Pi, you can also use the remote desktop function, which can help us manage the files in the Raspberry Pi easily.
For details on how to do this, please refer to Remote Desktop.
Projects¶
In this chapter, you will learn how to use RGB Matrix HAT and do some interesting projects.
Download the Code
Use the following command to download the code from the github repository.
git clone https://github.com/sunfounder/rgb_matrix
Note
Since RGB Matrix HAT uses I2C for communication, you need to do I2C Configuration before running the following projects.
Projects
Hello Matrix¶
In this project, you will learn how to make RGB Matix HAT display different patterns and characters in different colors.
Run the code
When the program runs, you will see a point, a line, a rectangle, an ellipse, and the text ‘Hi, SunFounder’ appears on the RGB Matrix HAT in turn.
cd /home/pi/rgb_matrix/raspberrypi
sudo python3 hello_matrix.py
Code
Note
You can Modify/Reset/Copy/Run/Stop the code below. But before that, you need to go to source code path like rgb_matrix/raspberrypi. After modifying the code, you can run it directly to see the effect.
from rgb_matrix import RGB_Matrix
import time
rr = RGB_Matrix(0x74) # create an RGB_Matrix object
point_coor = [3,1]
rr.draw_point(point_coor,fill=(255,255,0)) #draw a point
rr.display()
time.sleep(3)
line_coor = [0,2,7,2]
rr.draw_line(line_coor,fill=(255,0,0)) # draw a line
rr.display()
time.sleep(3)
rectangle_coor = [0,4,2,6]
rr.draw_rectangle(rectangle_coor,fill=(255,0,0)) #draw a rectangle
rr.display()
time.sleep(3)
ellipse_coor = [5,5]
radius = 2
rr.draw_ellipse(ellipse_coor,radius,fill=(0,255,0)) #draw a ellipse
rr.display() #display the picture which you draw
time.sleep(3)
text = 'Hi, SunFounder'
rr.show_text(text, delay=200,color=(0,0,255)) # show text
rr.display()
time.sleep(4)
How it works?
from rgb_matrix import RGB_Matrix
rr = RGB_Matrix(0x74)
Import the RGB_Matrix class, and then create its object rr for us to call its class member functions.
point_coor = [3,1]
rr.draw_point(point_coor,fill=(255,255,0)) #draw a point
rr.display()
time.sleep(3)
The above code is to display a yellow dot on the (3,1) coordinate of the RGB dot matrix.
draw_point() is a function that draws a point with 2 parameters: the first parameter is the coordinate on the RGB Matrix HAT, and the second parameter sets the color for the point.
The x,y coordinate directions of the dot matrix are as follows, with the first RGB LED in the upper left corner as the coordinate origin.
The fill tuple contains three elements R, G and B (red, green and blue) in the range 0-255. For example, when fill=(255,0,0), red is displayed. Refer to: https://www.rapidtables.com/web/color/RGB_Color.html for more color value combinations.
Once the coordinate and color are determined, the display() function is called to implement on the RGB dot matrix HAT.
line_coor = [0,2,7,2]
rr.draw_line(line_coor,fill=(255,0,0)) # draw a line
rr.display()
time.sleep(3)
The above code draws a red line starting at coordinate (0,2) and ending at (7,2).
draw_line() is a line drawing function, line_coor=[0,2,7,2] stores the coordinates of the start and end of the line (2 points determine a line). fill=(255,0,0) represents the line color is red.
rectangle_coor = [0,4,2,6]
rr.draw_rectangle(rectangle_coor,fill=(255,0,0)) #draw a rectangle
rr.display()
time.sleep(3)
The above code draws a red rectangle with coordinates (0, 4) and coordinates (2, 6) as diagonal coordinates.
draw_rectangle() is a function that draws a rectangle. The list rectangle_coor = [0,4,2,6] represents the two diagonal coordinates of the rectangle (0,4) and (2,6). The fill=(255,0,0) indicates that the rectangle color is red.
ellipse_coor = [5,5]
radius = 2
rr.draw_ellipse(ellipse_coor,radius,fill=(0,255,0)) #draw a ellipse
rr.display() #display the picture which you draw
time.sleep(3)
The above code draws a green circle with the coordinates (5,5) as the center and a radius of 2.
draw_ellipse() is a function that draws a circle with three arguments that determine the center, radius and color of the circle.
text = 'Hi, SunFounder'
rr.show_text(text, delay=200,color=(0,0,255)) # show text
rr.display()
time.sleep(4)
The above code is to move and display ‘Hi, SunFounder’ on the RGB Matrix HAT.
show_text() is used to display text information, text represents the string to be displayed, delay represents the moving time, the larger the value, the slower the text moving speed.
Dazzling Light¶
In the previous project, we learned to use some simple functions to make RGB Matrix HAT work. So here, we will use the draw_line() function with different colors to make RGB Matrix HAT make more cool effects.
Run the code
As the program runs, you will see the colors on the RGB Matrix HAT changing from right to left.
cd /home/pi/rgb_matrix/raspberrypi
sudo python3 dazzling_lights.py
Code
Note
You can Modify/Reset/Copy/Run/Stop the code below. But before that, you need to go to source code path like rgb_matrix/raspberrypi. After modifying the code, you can run it directly to see the effect.
from rgb_matrix import RGB_Matrix
import time
def ColorHSV(hue):
if hue < 510: # Red to Green-1
b = 0
if hue < 255: # Red to Yellow-1
r = 255
g = hue # g = 0 to 254
else: # Yellow to Green-1
r = 510 - hue # r = 255 to 1
g = 255
elif hue < 1020: # Green to Blue-1
r = 0
if hue < 765: # Green to Cyan-1
g = 255
b = hue - 510 # b = 0 to 254
else: # Cyan to Blue-1
g = 1020 - hue # g = 255 to 1
b = 255
elif hue < 1530: # Blue to Red-1
g = 0
if hue < 1275: # Blue to Magenta-1
r = hue - 1020 # r = 0 to 254
b = 255
else: # Magenta to Red-1
r = 255
b = 1530 - hue # b = 255 to 1
else: # Last 0.5 Red (quicker than % operator)
r = 255
g = b = 0
list = [r, g, b]
return list
def flash():
list = [[0, 0, 0, 7],
[1, 0, 1, 7],
[2, 0, 2, 7],
[3, 0, 3, 7],
[4, 0, 4, 7],
[5, 0, 5, 7],
[6, 0, 6, 7],
[7, 0, 7, 7]]
firsthue = 0
hue = 0
while firsthue < 1530:
j = 0
for i in list:
hue = firsthue + j * 95
j = j + 1
if hue > 1530:
hue = hue - 1530
temp = ColorHSV(hue)
#print(temp[0],temp[1],temp[2])
#time.sleep(2)
rr.draw_line(i, (temp[0], temp[1], temp[2]))
rr.display()
firsthue = firsthue + 11
if __name__ == "__main__":
rr = RGB_Matrix(0X74)
while True:
flash()
How it works?
In reality, there are three primary colors of red, yellow, and blue, and there are generally three primary colors of red, green, and blue in the display screen, that is, RGB. Their values are generally used FF0000,00FF00,0000FF means, converted to decimal is (255,0,0),(0,255,0),(0,0,255). This website can help us better understand the three primary colors.
def ColorHSV(hue):
if hue < 510: # Red to Green-1
b = 0
if hue < 255: # Red to Yellow-1
r = 255
g = hue # g = 0 to 254
else: # Yellow to Green-1
r = 510 - hue # r = 255 to 1
g = 255
elif hue < 1020: # Green to Blue-1
r = 0
if hue < 765: # Green to Cyan-1
g = 255
b = hue - 510 # b = 0 to 254
else: # Cyan to Blue-1
g = 1020 - hue # g = 255 to 1
b = 255
elif hue < 1530: # Blue to Red-1
g = 0
if hue < 1275: # Blue to Magenta-1
r = hue - 1020 # r = 0 to 254
b = 255
else: # Magenta to Red-1
r = 255
b = 1530 - hue # b = 255 to 1
else: # Last 0.5 Red (quicker than % operator)
r = 255
g = b = 0
list = [r, g, b]
return list
Reference from Adafruit_NeoPixel.
Because red is centered on the rollover point (the +32768 above, essentially a fixed-point +0.5), the above actually yields 0 to 1530, where 0 and 1530 would yield the same thing. Rather than apply a costly modulo operator, 1530 is handled as a special case below.
So you’d think that the color “hexcone” (the thing that ramps from pure red, to pure yellow, to pure green and so forth back to red, yielding six slices), and with each color component having 256 possible values (0-255), might have 1536 possible items (6*256), but in reality there’s 1530. This is because the last element in each 256-element slice is equal to the first element of the next slice, and keeping those in there this would create small discontinuities in the color wheel. So the last element of each slice is dropped…we regard only elements 0-254, with item 255 being picked up as element 0 of the next slice. Like this:
Red to not-quite-pure-yellow is: 255, 0, 0 to 255, 254, 0
Pure yellow to not-quite-pure-green is: 255, 255, 0 to 1, 255, 0
Pure green to not-quite-pure-cyan is: 0, 255, 0 to 0, 255, 254
and so forth.
Hence, 1530 distinct hues (0 to 1529), and hence why the constants below are not the multiples of 256 you might expect.
def flash():
list = [[0,0,0,7],
[1,0,1,7],
[2,0,2,7],
[3,0,3,7],
[4,0,4,7],
[5,0,5,7],
[6,0,6,7],
[7,0,7,7]]
The list list stores the starting and ending coordinates of the 8 vertical lines (from left to right), so that each line can be given a different color in the code later to achieve the colorful effect.
firsthue = 0
hue = 0
while firsthue < 1530:
j = 0
for i in list:
hue = firsthue + j*95
j = j + 1
if hue > 1530:
hue = hue-1530
temp = ColorHSV(hue)
rr.draw_line(i,(temp[0],temp[1],temp[2]))
rr.display()
firsthue = firsthue + 11
firshue and hue are passed to ColorHSV() as parameters.
Define a two-layer loop, the inner for loop is to draw eight lines in eight different colors,
The outer while loop is to add 11 to the hue values of the eight colors to achieve the effect of color flow.
For example, in the first for loop, 0, 95, 190, 285, 380, 475, 570, 665 are used as the hue value of the initial color of the 8 lines, and then enter the outer loop to increase the hue value of each line color by 11 to become 11, 106, 201, 296, 391, 486, 581, 676 to achieve the effect of line color sliding.
Moving Eye¶
In this project, we will use the draw_rectangle() and draw_point() functions to draw an eye pattern and achieve the effect of moving the eye around.
Run the code
When the program is running, you will see an eye moving around on the RGB matrix HAT.
cd /home/pi/rgb_matrix/raspberrypi
sudo python3 moving_eyes.py
Code
Note
You can Modify/Reset/Copy/Run/Stop the code below. But before that, you need to go to source code path like rgb_matrix/raspberrypi. After modifying the code, you can run it directly to see the effect.
from rgb_matrix import RGB_Matrix
import time
def up(list,step=1):
for i in range(0,step):
rr.draw_rectangle(list,fill=(251,248,40))
list[1] -= 1
list[3] -= 1
rr.draw_rectangle(list,fill=(0,0,0))
rr.display()
def down(list,step=1):
for i in range(0,step):
rr.draw_rectangle(list,fill=(251,248,40))
list[1] += 1
list[3] += 1
rr.draw_rectangle(list,fill=(0,0,0))
rr.display()
def left(list,step=1):
for i in range(0,step):
rr.draw_rectangle(list,fill=(251,248,40))
list[0] -= 1
list[2] -= 1
rr.draw_rectangle(list,fill=(0,0,0))
rr.display()
def right(list,step=1):
for i in range(0,step):
rr.draw_rectangle(list,fill=(251,248,40))
list[0] += 1
list[2] += 1
rr.draw_rectangle(list,fill=(0,0,0))
rr.display()
def left_down(list,step=1):
for i in range(0,step):
rr.draw_rectangle(list,fill=(251,248,40))
list[0] -= 1
list[2] -= 1
list[1] += 1
list[3] += 1
rr.draw_rectangle(list,fill=(0,0,0))
rr.display()
def left_up(list,step=1):
for i in range(0,step):
rr.draw_rectangle(list,fill=(251,248,40))
list[0] -= 1
list[2] -= 1
list[1] -= 1
list[3] -= 1
rr.draw_rectangle(list,fill=(0,0,0))
rr.display()
def right_up(list,step=1):
for i in range(0,step):
rr.draw_rectangle(list,fill=(251,248,40))
list[0] += 1
list[2] += 1
list[1] -= 1
list[3] -= 1
rr.draw_rectangle(list,fill=(0,0,0))
rr.display()
def right_down(list,step=1):
for i in range(0,step):
rr.draw_rectangle(list,fill=(251,248,40))
list[0] += 1
list[2] += 1
list[1] += 1
list[3] += 1
rr.draw_rectangle(list,fill=(0,0,0))
rr.display()
if __name__ == "__main__":
rr = RGB_Matrix(0X74)
rectangle_coor = [0,0,7,7]
rr.draw_rectangle(rectangle_coor,fill=(251,248,40))
point_arry = [[0,0],[1,0],[0,1],[6,0],[7,0],[7,1],[0,6],[0,7],[1,7],[7,6],[7,7],[6,7]]
for i in range(len(point_arry)):
rr.draw_point(point_arry[i],fill=(0,0,0))
list = [3,3,4,4]
rr.draw_rectangle(list,fill=(0,0,0),outline=None, width=0)
rr.display()
while True:
up(list,3)
down(list,6)
up(list,6)
down(list,6)
up(list,3)
time.sleep(1)
right_down(list,2)
up(list,4)
left(list,4)
down(list,4)
right(list,4)
left_up(list,2)
time.sleep(1)
How it works?
rectangle_coor = [0,0,7,7]
rr.draw_rectangle(rectangle_coor,fill=(251,248,40))
point_arry = [[0,0],[1,0],[0,1],[6,0],[7,0],[7,1],[0,6],[0,7],[1,7],[7,6],[7,7],[6,7]]
for i in range(len(point_arry)):
rr.draw_point(point_arry[i],fill=(0,0,0))
list = [3,3,4,4]
rr.draw_rectangle(list,fill=(0,0,0),outline=None, width=0)
rr.display()
The list
rectangle_coorrepresents a rectangle (the whole RGB dot matrix) from coordinates (0, 0) to (7, 7), and then use thedraw_rectangle()function to fill this rectangle with yellow.The list
point_arryrepresents the 12 points in the four corners, then use thedraw_point()function to set the color of each point to (0, 0, 0), i.e., extinguish these points. This depicts the outline of an eye.The
listrepresents a small rectangle from (3, 3) to (4, 4), and then use thedraw_rectangle()function to set the color of this rectangle to (0, 0, 0) to make the rectangle go out. This will describe the outline of the eyeball.Finally, the eye pattern is displayed on the RGB Matrix HAT using the
display()function.
while True:
up(list,3)
down(list,6)
up(list,6)
down(list,6)
up(list,3)
time.sleep(1)
right_down(list,2)
up(list,4)
left(list,4)
down(list,4)
right(list,4)
left_up(list,2)
time.sleep(1)
The main loop is to make the eyeball keep moving up and down, then turn one cycle, and finally return to the original position.
We call some functions to move the eyeball, for example up(list,3) is to move the eyeball up three squares, now look at how this function is implemented.
def up(list,step=1):
for i in range(0,step):
rr.draw_rectangle(list,fill=(251,248,40))
list[1] -= 1
list[3] -= 1
rr.draw_rectangle(list,fill=(0,0,0))
rr.display()
The up() function has 2 parameters list and step, the internal logic is to move the rectangle list up step squares (default is 1).
Define a
for()loop with the number of loops determined bystep. In thefor()loop, set the color of the rectanglelistto yellow.list = [3,3,4,4]are the 2 diagonal coordinates (3,3) and (4,4),list[1]andlist[3]are subtracted by one, meaning that the y-values of the 2 diagonal coordinates are subtracted by one.Then the modified
list = [3,2,4,3]color is set to (0,0,0) by the functiondraw_rectangle()and displayed on the dot matrix by the functiondisplay().After one for loop in this way, the pupil is moved up one square.
Christmas Tree¶
In this project, we will use the draw_point() function to make a colorful Christmas tree.
Run the code
When the program runs, you will see a shiny Christmas tree appear on the RGB Matrix HAT.
cd /home/pi/rgb_matrix/raspberrypi
sudo python3 christmas_tree.py
Code
Note
You can Modify/Reset/Copy/Run/Stop the code below. But before that, you need to go to source code path like rgb_matrix/raspberrypi. After modifying the code, you can run it directly to see the effect.
from rgb_matrix import RGB_Matrix
import time
from color import Color
def tree():
for i in green_coor:
rr.draw_point(i,(0,255,0))
for i in yellow_coor:
rr.draw_point(i,(255,255,0))
for i in red_coor:
rr.draw_point(i,(255,0,0))
rr.display()
def dot():
col = Color()
for i in flash_coor:
rr.draw_point(i,col.random())
rr.display()
if __name__ == "__main__":
rr = RGB_Matrix(0X74)
rectangle_coor = [0,0,7,7]
green_coor = [[3,0],[4,0],
[2,1],[3,1],[5,1],
[1,2],[2,2],[4,2],[5,2],[6,2],
[1,3],[2,3],[3,3],[4,3],[6,3],
[2,4],[4,4],[5,4],
[1,5],[3,5],[5,5],[6,5],
[1,6],[2,6],[3,6],[4,6],[5,6],[6,6]
]
flash_coor = [[4,1],[3,2],[5,3],[3,4],[2,5],[4,5]]
red_coor = [[0,3],[7,3],[0,6],[7,6]]
yellow_coor = [[3,0],[4,0],[3,6],[4,6],[3,7],[4,7]]
tree()
while True:
dot()
How it works?
from color import Color
Import the color class Color, which is a class that we encapsulate to manipulate RGB Matrix HAT colors. In this project, we will use a class function random() to display random colors.
green_coor = [[3,0],[4,0],
[2,1],[3,1],[5,1],
[1,2],[2,2],[4,2],[5,2],[6,2],
[1,3],[2,3],[3,3],[4,3],[6,3],
[2,4],[4,4],[5,4],
[1,5],[3,5],[5,5],[6,5],
[1,6],[2,6],[3,6],[4,6],[5,6],[6,6]]
flash_coor = [[4,1],[3,2],[5,3],[3,4],[2,5],[4,5]]
red_coor = [[0,3],[7,3],[0,6],[7,6]]
yellow_coor = [[3,0],[4,0],[3,6],[4,6],[3,7],[4,7]]
Divide the Christmas tree into four parts, the red part, the yellow part, the green part, and the blinking part, so we need four lists to store these coordinates.
def tree():
for i in green_coor:
rr.draw_point(i,(0,255,0))
for i in yellow_coor:
rr.draw_point(i,(255,255,0))
for i in red_coor:
rr.draw_point(i,(255,0,0))
rr.display()
Define a tree() function to draw the green(0, 255, 0), yellow(255, 255, 0) and red(255, 0, 0) parts of the Christmas tree.
def dot():
col = Color()
for i in coor:
rr.draw_point(i,col.random())
rr.display()
For the blinking points in the Christmas tree, we can use the random() function in the Color class to achieve. The function of random() is to return a random RGB value, that is, to display random colors in a loop to achieve a blinking effect.
tree()
while True:
dot()
Finally, two functions are called to draw the Christmas tree. The blinking is continuous, so dot() should be called in the loop.
Greedy Snake¶
In this project, we use the RGB matrix HAT as the display screen to create a snake eating game by reading the values of the keyboard keys to change the display effect.
Run the code
When the program runs, the snake game starts, the keyboard a and d controls the snake to turn left and right.
Each time the snake eats a bean, score plus one. When it encounters itself, the score returns to zero.
After a period of time, the screen will turn blue, and the score will be displayed after a while. Press q to end the game, and Ctrl+C to exit the program.
cd /home/pi/rgb_matrix/raspberrypi
sudo python3 snake_game.py
Code
You can view the code by typing the command nano snake_game.py in Terminal or by clicking on github-snake_game.py.
How it works?
def readchar():
fd = sys.stdin.fileno()
old_settings = termios.tcgetattr(fd)
try:
tty.setraw(sys.stdin.fileno())
ch = sys.stdin.read(1)
finally:
termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
return ch
This function is used to read keyboard input and return the entered characters.
def Keyboard_control():
while True:
global power_val,key
# key = 'n'
key=readkey()
time.sleep(0.22)
if key=='q':
print("quit")
break
Keyboard_control() is used for keyboard control. Call readkey() in an infinite loop to receive the characters input by the keyboard. In addition, the logic of snake-eating is also an infinite loop, then multithreading may be needed when there are multiple infinite loops in a program.
def snake_game():
global key
rr = RGB_Matrix(0X74)
rectangle_coor = [0,0,7,7]
#rr.draw_rectangle(rectangle_coor,fill=(51,51,0)) #draw a rectangle
coor_1 = np.asarray([0,2])
coor_2 = np.asarray([1,2])
coor_3 = np.asarray([2,2])
coor_4 = np.asarray([3,2])
coor_list = [coor_1,coor_2,coor_3,coor_4]
...
snake_game() is used to represent snake-eating logic. The received key value is a character entered by the keyboard, which needs to be declared as a global variable with globla.
There are three main parts of snake logic:
In the first part, when the
aordkey is not pressed, first judge the horizontal and vertical, and then judge the forward direction, and then add 1 or subtract 1 to the horizontal or vertical coordinates of each point to achieve the effect of moving up, down, left, and right.The second part is to judge whether the
aordkey is pressed. If yes, then judge the horizontal and vertical direction and then determine the forward direction, and then add one or subtract one to the coordinates of each point of the snake head, and the snake head coordinates are additionally processed to achieve the effect of turning the head.The third part is to determine whether the snake head is in contact with dot. If yes, set
eat_flagtoFalseand add an element to the list of snakes to achieve the effect of growing snakes.
if __name__ == "__main__":
t1 = threading.Thread(target=Keyborad_control)
t2 = threading.Thread(target=snake_game)
t1.setDaemon(True)
t2.setDaemon(True)
t1.start()
t2.start()
while True:
pass
The Thread method in the threading ``class can help us create a thread, and the parameter is ``target=function name.
SetDaemon(True)sets the thread as a daemon thread. It is generally used in an unimportant thread with an infinite loop.Start()starts the thread.
Camera Recognition¶
In this project, we will make a color recognizer, connect a camera module to the Raspberry Pi, use PiCamera and OpenCV to process the objects captured by the camera, and express its colors with RGB Matrix HAT.
Note
This example needs to enable the Raspberry Pi Camera function.
Then install third-party dependencies
sudo pip3 install opencv-contrib-python
sudo apt-get install -y python3-h5py libatlas-base-dev
sudo pip3 install -U numpy
Run the code
When the program is running, hold the camera moduel and aim at some brightly colored objects, you will find that the RGB Matrix HAT also shows similar colors.
cd /home/pi/rgb_matrix/raspberrypi
sudo python3 camera.py
Code
Note
You can Modify/Reset/Copy/Run/Stop the code below. But before that, you need to go to source code path like rgb_matrix/raspberrypi. After modifying the code, you can run it directly to see the effect.
# To run this example, you need to turn on Camera on raspi-config => Interfacing => Camera
# Then run the following command to install dependencies
# sudo pip3 install opencv-contrib-python
# sudo apt-get install -y python3-h5py libatlas-base-dev
# sudo pip3 install -U numpy
from picamera.array import PiRGBArray # Generates a 3D RGB array
from picamera import PiCamera
import time
import cv2
from PIL import Image
from rgb_matrix import RGB_Matrix
rr = RGB_Matrix(0X74)
camera = PiCamera()
camera.resolution = (1280, 720)
raw_capture = PiRGBArray(camera, size=(1280, 720))
# Allow the camera to warmup
time.sleep(0.1)
# Grab an image from the camera
for frame in camera.capture_continuous(raw_capture, format="rgb", use_video_port=True):
image = frame.array
# Convert image to 8x8 for RGB matrix
img = cv2.resize(image, (8, 8), interpolation = cv2.INTER_AREA)
im_pil = Image.fromarray(img)
# Render
rr.image(list(im_pil.getdata()))
raw_capture.truncate(0)
How it works?
from picamera.array import PiRGBArray # Generates a 3D RGB array
from picamera import PiCamera
import time
import cv2
from PIL import Image
from rgb_matrix import RGB_Matrix
Import
PiCamerato support the use of the camera.Import
PiRGBArrayto help the Raspberry Pi output the captured images in the form of an array.Import
OpenCVvision library wherecv2`is the name of the C++ namespace of Opencv.Import the image processing library
PILof the python platform.
camera = PiCamera()
camera.resolution = (1280, 720)raw_capture = PiRGBArray(camera, size=(1280, 720))
Create a PiCamera object and call PiRGBArray() to generate an RGB three-dimensional array with a resolution of (1280, 720) and pass it to raw_capture.
for frame in camera.capture_continuous(raw_capture, format="rgb", use_video_port=True):
image = frame.array
Traverse the images captured by the camera and pass them to the image in the form of an RGB three-dimensional array.
img = cv2.resize(image, (8, 8), interpolation = cv2.INTER_AREA)
im_pil = Image.fromarray(img)
Convert the picture into an 8x8 RGB Matrix HAT and pass it to im_pil in the form of an array.
rr.image(list(im_pil.getdata()))
Convert im_pil into a list form to be used as a parameter of rr.image to light up the RGB Matrix HAT.
raw_capture.truncate(0)
Clear raw_capture in this loop.
Custom Shape¶
In the previous project, we made a Christmas tree with point coordinates. In this project, we used straight lines to piece together a pattern of Pac-Man.
Run the code
When the program runs, you will see a Pac-Man appearing on the RGB Matrix HAT, and its mouth is continuously opening and closing.
cd /home/pi/rgb_matrix/raspberrypi
sudo python3 custom_shape.py
Code
Note
You can Modify/Reset/Copy/Run/Stop the code below. But before that, you need to go to source code path like rgb_matrix/raspberrypi. After modifying the code, you can run it directly to see the effect.
from rgb_matrix import RGB_Matrix
import time
import random
def pacman():
rectangle_coor = [0,0,7,7]
list = [[2,0,5,0],
[1,1,6,1],
[0,2,1,2],
[3,2,5,2],
[0,3,4,3],
[0,4,4,4],
[0,5,5,5],
[1,6,6,6],
[2,7,5,7]]
fill = (144,192,22)
for i in list:
rr.draw_line(i,fill)
rr.display()
time.sleep(1)
rr.draw_rectangle(rectangle_coor,fill=(0,0,0))
def pacman2():
rectangle_coor = [0,0,7,7]
list = [[2,0,5,0],
[1,1,6,1],
[0,2,1,2],
[3,2,7,2],
[0,3,7,3],
[0,4,3,4],
[0,5,7,5],
[1,6,6,6],
[2,7,5,7]]
fill = (144,192,22)
for i in list:
rr.draw_line(i,fill)
rr.display()
time.sleep(1)
rr.draw_rectangle(rectangle_coor,fill=(0,0,0))
if __name__ == "__main__":
rr = RGB_Matrix(0X74)
rectangle_coor = [0,0,7,7]
while True:
pacman()
time.sleep(0.5)
pacman2()
How it works?
def pacman():
rectangle_coor = [0,0,7,7]
list = [[2,0,5,0],
[1,1,6,1],
[0,2,1,2],
[3,2,5,2],
[0,3,4,3],
[0,4,4,4],
[0,5,5,5],
[1,6,6,6],
[2,7,5,7]]
def pacman2():
rectangle_coor = [0,0,7,7]
list = [[2,0,5,0],
[1,1,6,1],
[0,2,1,2],
[3,2,7,2],
[0,3,7,3],
[0,4,3,4],
[0,5,7,5],
[1,6,6,6],
[2,7,5,7]]
Define two functions pacman() and pacman2() to represent the two states of Pac-Man. These two states are composed of many lines, and two lists are defined to store the starting and ending coordinates of these lines respectively. rectangle_coor represents the entire RGB matrix HAT, which can be used to clear the screen.
fill = (144,192,22)
for i in list:
rr.draw_line(i,fill)
rr.display()
time.sleep(1)
rr.draw_rectangle(rectangle_coor,fill=(0,0,0))
The above code exists in both functions pacman() and pacman2() and is used to display the 2 states of Pac-Man in yellow in the RGB Matrix HAT and then clear the screen.
while True:
pacman()
time.sleep(0.5)
pacman2()
Call pacman() and pacman2() cyclically to increase the dynamic effect of Pac-Man.
You can also imagine other more interesting patterns, this website may be able to get some references.
Custom Dynamic Shape¶
Here, based on the previous project, a continuous animation of Pac-Man eating dots will be created.
Run the code
When the program is running, you will see Pac-Man on the RGB matrix cap move from left to right and leave after eating the rightmost dot.
cd /home/pi/rgb_matrix/raspberrypi
sudo python3 custom_dynamic_shape.py
Code
Note
You can Modify/Reset/Copy/Run/Stop the code below. But before that, you need to go to source code path like rgb_matrix/raspberrypi. After modifying the code, you can run it directly to see the effect.
from rgb_matrix import RGB_Matrix
import time
import random
def pacman(a,k):
list2 = [[a-4,0,a-1,0],
[a-5,1,a,1],
[a-6,2,a-5,2],
[a-3,2,a-1,2],
[a-6,3,a-2,3],
[a-6,4,a-2,4],
[a-6,5,a-1,5],
[a-5,6,a,6],
[a-4,7,a-1,7]]
fill = (144,192,22)
for i in range(0,k+1):
for j in list2:
rr.draw_line(j,fill)
rr.display()
for j in list2:
rr.draw_line(j,fill=(0,0,0))
for i in range(0,9):
list2[i][0] += 1
list2[i][2] += 1
time.sleep(0.1)
def pacman2():
rr.draw_rectangle(rectangle_coor,fill=(0,0,0))
list = [[2,0,5,0],
[1,1,6,1],
[0,2,1,2],
[3,2,7,2],
[0,3,7,3],
[0,4,3,4],
[0,5,7,5],
[1,6,6,6],
[2,7,5,7]]
fill = (144,192,22)
for i in list:
rr.draw_line(i,fill)
rr.display()
time.sleep(0.1)
rr.draw_rectangle(rectangle_coor,fill=(0,0,0))
def pac():
coor = [6,3,7,4]
rr.draw_rectangle(coor,fill=(82,52,25))
if __name__ == "__main__":
rr = RGB_Matrix(0X74)
rectangle_coor = [0,0,7,7]
while True:
pac()
pacman(0,6)
pacman2()
pacman(6,7)
How it works?
while True:
pac()
pacman(0,6)
pacman2()
pacman(6,7)
We can disassemble Pac-Man into three actions, pac() represents the position of the dot.
pacman(0,6)means that Pac-Man moves from the far left to the side of the dot.pacman2()mouth closed to indicate the action of eating.pacman(6,7)indicates to continue to leave after eating.
def pacman(a,k):
list2 = [[a-4,0,a-1,0],
[a-5,1,a,1],
[a-6,2,a-5,2],
[a-3,2,a-1,2],
[a-6,3,a-2,3],
[a-6,4,a-2,4],
[a-6,5,a-1,5],
[a-5,6,a,6],
[a-4,7,a-1,7]]
fill = (144,192,22)
for i in range(0,k+1):
for j in list2:
rr.draw_line(j,fill)
rr.display()
for j in list2:
rr.draw_line(j,fill=(0,0,0))
for i in range(0,9):
list2[i][0] += 1
list2[i][2] += 1
time.sleep(0.1)
The pacman() function is used to make Pac-man move from the left to the right in an open-mouthed state until it disappears. It has two parameters a and k, a represents the starting position of Pac-man and k represents the number of squares moved to the right.
list2stores the coordinates of Pac-man’s open-mouth state, drawn as lines, with the x-coordinate of each line determined bya.Define a two-level for loop. The inner loop does three things: draws Pac-Man, moves each line in
list2one square to the right, and removes the movement.The outer layer repeats the loop
ktimes, which means Pac-Man movesksquares to the right.
Appendix¶
I2C Configuration¶
Step 1: Enable the I2C port of your Raspberry Pi (If you have enabled it, skip this; if you do not know whether you have done that or not, please continue).
sudo raspi-config
3 Interfacing options
P5 I2C
<Yes>, then <Ok> -> <Finish>
Step 2: Check whether the i2c modules are loaded and active.
lsmod | grep i2c
Then the following codes will appear (the number may be different).
i2c_dev 6276 0
i2c_bcm2708 4121 0
Step 3: Install i2c-tools.
sudo apt-get install i2c-tools
Step 4: Check the address of the I2C device.
i2cdetect -y 1 # For Raspberry Pi 2 and higher version
i2cdetect -y 0 # For Raspberry Pi 1
pi@raspberrypi ~ $ i2cdetect -y 1
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- 48 -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
If there is an I2C device connected, the address of the device will be displayed.
Remote Desktop¶
There are two ways to control the desktop of the Raspberry Pi remotely:
VNC and XRDP, you can use any of them.
VNC¶
You can use the function of remote desktop through VNC.
Enable VNC service
The VNC service has been installed in the system. By default, VNC is disabled. You need to enable it in config.
Step 1
Input the following command:
sudo raspi-config
Step 2
Choose 3 Interfacing Options by press the down arrow key on your keyboard, then press the Enter key.
Step 3
P3 VNC
Step 4
Select Yes -> OK -> Finish to exit the configuration.
Login to VNC
Step 1
You need to download and install the VNC Viewer on personal computer. After the installation is done, open it.
Step 2
Then select “New connection”.
Step 3
Input IP address of Raspberry Pi and any Name.
Step 4
Double click the connection just created:
Step 5
Enter Username (pi) and Password (raspberry by default).
Step 6
Now you can see the desktop of the Raspberry Pi:
That’s the end of the VNC part.
XRDP¶
Another method of remote desktop is XRDP, it provides a graphical login to remote machines using RDP (Microsoft Remote Desktop Protocol).
Install XRDP
Step 1
Login to Raspberry Pi by using SSH.
Step 2
Input the following instructions to install XRDP.
sudo apt-get update
sudo apt-get install xrdp
Step 3
Later, the installation starts.
Enter “Y”, press key “Enter” to confirm.
Step 4
Finished the installation, you should login to your Raspberry Pi by using Windows remote desktop applications.
Login to XRDP
Step 1
If you are a Windows user, you can use the Remote Desktop feature that comes with Windows. If you are a Mac user, you can download and use Microsoft Remote Desktop from the APP Store, and there is not much difference between the two. The next example is Windows remote desktop.
Step 2
Type in “mstsc” in Run (WIN+R) to open the Remote Desktop Connection, and input the IP address of Raspberry Pi, then click on “Connect”.
Step 3
Then the xrdp login page pops out. Please type in your username and password. After that, please click “OK”. At the first time you log in, your username is “pi” and the password is “raspberry”.
Step 4
Here, you successfully login to RPi by using the remote desktop.
Copyright Notice¶
All contents including but not limited to texts, images, and code in this manual are owned by the SunFounder Company. You should only use it for personal study,investigation, enjoyment, or other non-commercial or nonprofit purposes, under therelated regulations and copyrights laws, without infringing the legal rights of the author and relevant right holders. For any individual or organization that uses these for commercial profit without permission, the Company reserves the right to take legal action.