Trouble Using DMA on the RP2350 (Pico2)

[TheFargo]

Hello friends! I'm trying to set up the DMA in MicroPython and I'm seeing some funny errors? Is the DMA code working on the new RP2350s? Does anyone have any working code I can look at? Here's what I've tried and what I'm seeing:

Simply trying to initialize a DMA channel with the DMA class throws an error as though the class doesn't exist:
'''py
import rp2
dma = rp2.DMA()
'''
Generates this error:
An error occurred: 'int' object isn't callable

I have gotten this result in both 1.25 and the 1.26 preview.

Another problem I've noticed (unsure if related!) is that I can't reset the DMA. If I use MEM32 to manually flip the reset bit, it doesn't seem to change. (?) I can provide sample code for that if needed.

Mostly I'd just like to know if anyone else is having problems with the DMA in the RP2350 and how they solved them? Thank you!!

[TheFargo]

(I saw this thread: https://github.com/orgs/micropython/discussions/17390 but that seems to be a slightly different issue, I started a new thread here when the previous one didn't seem to fix my issue!)

[TheFargo]

Thank you for replying! I tried these lines in the REPL and I got the same result as you, it worked fine.

import rp2
dma = rp2.DMA()
print(dma)
DMA(0)

I can't imagine why it's erroring out in code.

[GitHubsSilverBullet]

I'd wager that somewhere in there the name ›DMA‹ is assigned an integer value.
Hence the: ›An error occurred: 'int' object isn't callable‹

[TheFargo]

You would think that was the case from the error message! But the error appears to be generated from inside the MicroPython DMA routine.

Here is the entirety of my test code:

from rp2 import DMA
print("DMA Instantiation Test")
try:
    dma_channel = DMA()
    print(f"SUCCESS! Created DMA object channel {dma_channel.channel()}.")
    dma_channel.close()
    print("DMA channel closed.")
except Exception as e:
    print(f"An unexpected error occurred: {e}")

And the result:
DMA Instantiation Test
An unexpected error occurred: 'int' object isn't callable

What is happening that allows this code to run in REPL but not in this program? I've tried both 1.25 and 1.26 on two different PICO 2 units with the same mysterious error.

[GitHubsSilverBullet]

Here's your problem:dma_channel.channel()

channel is not a class method, channel is a property.
Therefore:
print(f"SUCCESS! Created DMA object channel { dma_channel.channel }.")
Without the brackets.

[TheFargo]

Thank you, Silver Bullet! I can't believe I was throwing an error with a stupid print statement - probably for a few iterations of my code now, trying to figure it out. Appreciate the help!