SunFounder Thales Kit, Manual

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SunFounder Thales Kit for Raspberry Pi Pico, Release 1.0
2. Insert 74HC595 across the middle gap into the breadboard.
3. Connect the GP0 pin of Pico to the DS pin (pin 14) of 74HC595 with a jumper wire.
4. Connect the GP1 pin of Pico to the STcp pin (12-pin) of 74HC595.
5. Connect the GP2 pin of Pico to the SHcp pin (pin 11) of 74HC595.
6. Connect the VCC pin (16 pin) and MR pin (10 pin) on the 74HC595 to the positive power bus.
7. Connect the GND pin (8-pin) and CE pin (13-pin) on the 74HC595 to the negative power bus.
8. Insert 8 LEDs on the breadboard, and their anode leads are respectively connected to the Q0~Q1 pins (15, 1, 2,
3, 4, 5, 6, 7) of 74HC595.
9. Connect the cathode leads of the LEDs with a 220 resistor in series to the negative power bus.
Code
import machine
import time
sdi = machine . Pin( 0 ,machine . Pin . OUT)
rclk = machine . Pin( 1 ,machine . Pin . OUT)
srclk = machine . Pin( 2 ,machine . Pin . OUT)
def hc595_shift (dat):
rclk . low()
time . sleep_ms( 5 )
for bit in range ( 7 , - 1 , - 1 ):
srclk . low()
time . sleep_ms( 5 )
value = 1 & (dat >> bit)
sdi . value(value)
time . sleep_ms( 5 )
srclk . high()
time . sleep_ms( 5 )
time . sleep_ms( 5 )
rclk . high()
time . sleep_ms( 5 )
num = 0
for i in range ( 16 ):
if i < 8 :
num = (num << 1 ) + 1
elif i >= 8 :
num = (num & 0b01111111 ) << 1
hc595_shift(num)
print ( "{:0>8b}" . format(num))
time . sleep_ms( 200 )
When the program is running,
num
will be written into the 74HC595 chip as an eight-bit binary number to control the
on and off of the 8 LEDs. We can see the current value of
num
in the shell.
3.4. Projects 97