QUERY · ISSUE

Black Cat in a Coal Bunker

openby kevindawsonopened 2021-04-13updated 2021-08-20

μpython v1.14 on 2021-04-09 (GNU 10.2.0 MinSizeRel)

from - Raspberry Pi Pico Python SDK (2021-04-07)
The idea is that for the 4 sets of pins ( in , out , set , sideset , excluding jmp ) that can be connected to a state machine,
there’s the following that need configuring for each set:

Sample code:

from rp2 import PIO, StateMachine, asm_pio
from machine import Pin

@asm_pio(set_pins=(PIO.OUT_LOW, PIO.OUT_HIGH,  PIO.IN_LOW), sideset_pins=PIO.OUT_LOW)
def foo():
    pass

sm0 = StateMachine( 0, foo, freq=2000, set_pins=Pin(15), sideset_pins=Pin(22))

it just produces errors

Traceback (most recent call last):
  File "<stdin>", line 5, in <module>
  File "rp2.py", line 230, in asm_pio
TypeError: unexpected keyword argument 'set_pins'

I can find info -> machine -> https://docs.micropython.org/en/latest/library/machine.html
but info for rp2 -> null

looking in the rp2 stubs - StateMachine

def __init__(self, id, prog, freq: int=-1, *, in_base: Pin=None, out_base: Pin=None, set_base: Pin=None, jmp_pin: Pin=None, sideset_base: Pin=None, in_shiftdir: int=None, out_shiftdir: int=None, push_thresh: int=None, pull_thresh: int=None):

Ureka - moment - there NO set_pins in StateMachine instantiation

from rp2 import PIO, StateMachine, asm_pio
from machine import Pin

@asm_pio(set_pins=(PIO.OUT_LOW, PIO.OUT_HIGH,  PIO.IN_LOW), sideset_pins=PIO.OUT_LOW)
def foo():
    pass

sm0 = StateMachine( 0, foo, freq=2000, set_base=Pin(15), out_base=Pin(16), sideset_base=Pin(22))

looking in the rp2 stubs - asm_pio

def asm_pio(set_init: int = None, out_shiftdir: int = None, autopull: bool = None, pull_thresh: int = None, set_pins: Iterable[Sequence[int]] = None, sideset_pins: int = None, sideset_init: int = None, out_init: int = None, autopush: bool = None, push_thresh: int = None, in_base: int = None, out_base: int = None) -> Any:

Just hit the brick wall:(

Any chance someone that knows can put a working example up:
The idea is that for the 4 sets of pins ( in , out , set , sideset , excluding jmp ) that can be connected to a state machine,
there’s the following that need configuring for each set:

base GPIO
number of consecutive GPIO
initial GPIO direction (in or out pin)
initial GPIO value (high or low)

or do I need to add a documentation request -> Roadmap to next release v1.15

Thanks in Adv.

CANDIDATE · ISSUE

RP2350: PIO2 State Machines do not work

closedby IntergalacticMicrosystemsopened 2025-06-17updated 2025-08-01

bugport-rp2

Port, board and/or hardware

ports-rp2 Pico 2

MicroPython version

MicroPython v1.26.0-preview.251.g5ade8b705 on 2025-06-16; Raspberry Pi Pico2 with RP2350

Reproduction

pio_1hz.py from examples does not blink the LED or trigger the interrupt when switched to StateMachine IDs 8, 9, 10, or 11.

Expected behaviour

No response

Observed behaviour

What I've found so far:
PIO2_BASE + SM0_EXECCTRL is set incorrectly
PIO2 instruction memory is not loaded
Instruction start address is not set

Additional Information

This code mostly works.
The IRQ handler only triggers once, not repeatedly as expected.

import time
from machine import Pin
import rp2

@rp2.asm_pio(set_init=rp2.PIO.OUT_LOW)
def blink_1hz():
    # fmt: off
    # Cycles: 1 + 1 + 6 + 32 * (30 + 1) = 1000
    irq(rel(0))
    set(pins, 1)
    set(x, 31)                  [5]
    label("delay_high")
    nop()                       [29]
    jmp(x_dec, "delay_high")

    # Cycles: 1 + 1 + 6 + 32 * (30 + 1) = 1000
    nop()
    set(pins, 0)
    set(x, 31)                  [5]
    label("delay_low")
    nop()                       [29]
    jmp(x_dec, "delay_low")
    # fmt: on


# Create the StateMachine with the blink_1hz program, outputting on Pin(25).
sm = rp2.StateMachine(8, blink_1hz, freq=2300, set_base=Pin(25))

# Set the IRQ handler to print the millisecond timestamp.
sm.irq(lambda p: print(time.ticks_ms()))

# -------- MANUAL REGISTER SETTING START -----------
import machine
PIO2_BASE = 0x50400000
SM0_EXECCTRL = 0xCC
INSTR_MEM0 = 0x48
SM0_INSTR = 0xD8
machine.mem32[PIO2_BASE + SM0_EXECCTRL] = 129920
instrs = [49168, 57345, 58687, 48450, 89, 41026, 57344, 58687, 48450, 94]
instr_start = 0x48 + (4 * (32-len(instrs)))
for idx,instr in enumerate(instrs):    
    machine.mem32[PIO2_BASE + instr_start + (idx*4)] = instr
machine.mem32[PIO2_BASE + SM0_INSTR]=32-len(instrs)
# -------- MANUAL REGISTER SETTING END -----------

# Start the StateMachine.
sm.active(1)

while(True):
    pass

Code of Conduct

Yes, I agree