Control Servo Position Using a Raspberry Pi Pico PIO State Machine

In this video tutorial we show you how you can use a Raspberry Pi Pico PIO Statemachine to control the position of a servo. For your convenience, the code from this lesson is presented below. Enjoy!

from machine import Pin
import rp2
@rp2.asm_pio(set_init=rp2.PIO.OUT_LOW,out_shiftdir=rp2.PIO.SHIFT_RIGHT)
def servoSet():
    set(x,0b11111)
    in_(x,5)
    set(x,0b0100)
    in_(x,4)
    #set(x,0b00000)
    #in_(x,1)
    mov(osr,isr)
    
    mov(isr,null)
    set(y,0b10011)
    in_(y,5)
    set(y,0b10001)
    in_(y,5)
    set(y,0b00000)
    in_(y,5)
    
    wrap_target()
    mov(x,osr)
    mov(y,isr)
    set(pins,0)
    label('timeLoop')
    jmp(x_not_y,'nxt')
    set(pins,1)
    label('nxt')
    jmp(y_dec,'timeLoop')    
    wrap()
    
sm0 = rp2.StateMachine(0,servoSet, freq=2000000, set_base=Pin(20))
sm0.active(1)

from machine import Pin

import rp2

@rp2.asm_pio(set_init=rp2.PIO.OUT_LOW,out_shiftdir=rp2.PIO.SHIFT_RIGHT)

def servoSet():

set(x,0b11111)

in_(x,5)

set(x,0b0100)

in_(x,4)

#set(x,0b00000)

#in_(x,1)

mov(osr,isr)

mov(isr,null)

set(y,0b10011)

in_(y,5)

set(y,0b10001)

in_(y,5)

set(y,0b00000)

in_(y,5)

wrap_target()

mov(x,osr)

mov(y,isr)

set(pins,0)

label('timeLoop')

jmp(x_not_y,'nxt')

set(pins,1)

label('nxt')

jmp(y_dec,'timeLoop')

wrap()

sm0 = rp2.StateMachine(0,servoSet, freq=2000000, set_base=Pin(20))

sm0.active(1)

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