QUERY · ISSUE

rp2 asm_pio parameterization

openby odewdneyopened 2021-10-15updated 2026-03-24

enhancementport-rp2

Hi,

I would like to pass parameters into the RP2 assembler to configure the generated code, eg adjust a delay loop, change number of bits shifted etc.

I propose an additional parameter to the asm_pio function decorator 'vars' that takes a dictionary, that gets added to the global context that assembler runs in eg:

@asm_pio(vars={"DELAY":10})
def statemachine():
  label("wait")
  set(x,DELAY)
  jmp(x_dec,"wait")

with an addition of gl.update(vars) in the asp_pio dec function

CANDIDATE · ISSUE

rp2 import PIO, StateMachine, asm_pio -> Info -> 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.

rp2 asm_pio parameterization

rp2 import PIO, StateMachine, asm_pio -> Info -> Black Cat in a Coal Bunker

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