Freenove Ultimate Starter Kit, Руководство пользователя

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283 Chapter 27 Solder Circuit Board █ www.freenove.com
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Python Code 27.2.1 LightWater03
First observe the project result, and then analyze the code.
1.
Use cd command to enter 27.2.1_LightWater03 directory of Python code.
cd ~/Freenove_Ultimate_Starter_Kit_for_Raspberry_Pi/Code/Python_Code/27.2.1_LightWater03
2. Use python command to execute python code “LightWater03.py”.
python LightWater03.py
After the program is executed, the LEDs will light up in the form of flowing water and carry a long tail.
The following is the program code:
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i m port RPi . GPIO a s GPIO
i m port time
LSBFIRST = 1
MSBFIRST = 2
#define the pins connect to 74HC595
dataPin = 11 #DS Pin of 74HC595(Pin14)
latchPin = 13 #ST_CP Pin of 74HC595(Pin12)
clockPin = 15 #SH_CP Pin of 74HC595(Pin11)
#Define an array to save the pulse width of LED. Output the signal to the 8 adjacent LEDs
in order.
pluseWidth = [ 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 64 , 32 , 16 , 8 , 4 , 2 , 1 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 ]
d e f setup ( ):
GPIO . setmode ( GPIO . BOARD ) # Number GPIOs by its physical location
GPIO . setup ( dataPin , GPIO . OUT )
GPIO . setup ( latchPin , GPIO . OUT )
GPIO . setup ( clockPin , GPIO . OUT )
d e f shiftOut ( dPin , cPin , order , val ):
f o r i i n range ( 0 , 8 ):
GPIO . output ( cPin , GPIO . LOW );
i f ( order = = LSBFIRST ):
GPIO . output ( dPin ,( 0x01 &( val >> i )== 0x01 ) a n d GPIO . HIGH o r GPIO . LOW )
e l if ( order = = MSBFIRST ):
GPIO . output ( dPin ,( 0x80 &( val << i )== 0x80 ) a n d GPIO . HIGH o r GPIO . LOW )
GPIO . output ( cPin , GPIO . HIGH );
d e f outData ( data ):
GPIO . output ( latchPin , GPIO . LOW )
shiftOut ( dataPin , clockPin , LSBFIRST , data )
GPIO . output ( latchPin , GPIO . HIGH )
d e f loop ( ):
moveSpeed = 0.1 #move speed delay, the larger, the slower
index = 0 #Starting from the array index 0