Port, board and/or hardware

rp2 / rp2040

MicroPython version

MicroPython v1.27.0 on 2025-12-09; Raspberry Pi Pico with RP2040

Reproduction

Run the following code:

from rp2 import DMA

def dma_in_handler(dma):
    pass 

buf_src = bytearray(20)
buf_in = bytearray(20)

dma_in = DMA()
dma_in_ctrl = dma_in.pack_ctrl(size=0, treq_sel=0)
dma_in.irq(dma_in_handler, False)
dma_in.config(
    read=buf_src,
    write=buf_in,
    count=20,
    ctrl=dma_in_ctrl,
    trigger=True
)

#dma_in.active(False)
#dma_in.irq(None)

print("Hello")

Now attempt to soft-reboot the device (e.g. Ctrl-D on REPL). The device becomes unresponsive and requires a hard reboot.

• Calling dma_in.active(False) before exit avoids the problem
• Calling dma_in.irq(None) before exit avoids the problem
• Removing the treq_sel parameter avoids the problem (presumably because the DMA is then inactive at the time of reboot)

Expected behaviour

No response

Observed behaviour

Device becomes unresponsive over serial after program is run and then MP is soft-rebooted.

Additional Information

No, I've provided everything above.

Code of Conduct

Yes, I agree