Intelligent trash can (VII) -- Introduction and use of sg90 steering gear (Pico implementation of raspberry pie)

One 、SG90 Pin introduction of steering gear

Three wires will be led out of the steering gear ： Namely GND（ Brown line ）、VCC（ Red thread ） and SIG（ Yellow line ）, It's the ground wire 、 power cord （5V） And signal line . Never get it wrong ！

Two 、 And pico Pin docking

yellow （ cable ） —>GPIO0
Brown （ The bottom line GND） —>VBUS
Red （ power cord VCC） —>GND

3、 ... and 、 Operating principle of steering gear

1638-8192(0-180)

sg90 principle : stay 50hz The period at frequency is 20ms

t = 0.5ms——————- The rudder turns 0 °
t = 1.0ms——————- The rudder turns 45°
t = 1.5ms——————- The rudder turns 90°
t = 2.0ms——————- The rudder turns 135°
t = 2.5ms——————- The rudder turns 180°
duty_u16 computing method ,90 Degree time 65532*1.5/20 Get the value of the ,

Four 、Thonny Program

from machine import PWM,Pin
import utime
s = PWM(Pin(0))
s.freq(50)
s.duty_u16(4915)  # 4915 yes 90 degree 
utime.sleep(2)
s.duty_u16(8192)  # 8192 yes 180 degree 
utime.sleep(2)
s.duty_u16(1638)  # 1638 yes 0 degree 

5、 ... and 、 Effect display