“WebMiteRP2350V6.04.00RC1_RM2.uf2 file fixes the Wi-Fi problem.  See Patch Report.
It works with WeAct & RM2 and Pico2 W. Not with Waveshare RP2350B-Plus-W.
Manual, page 81 describes  the Problem "With some routers it can take some time or a couple of attempts to connect, so if you are using OPTION
AUTORUN ON, it would be worth inserting something like this at the very start of your program:
DO WHILE MM.INFO(IP ADDRESS) = "0.0.0.0"
IF TIMER > 5000 THEN CPU RESTART
LOOP
This would wait 5 seconds for a connection and restart
if still not connected."
WebMite_RP2350B_RM2_WiFi_Patch_Report.pdf

WebMiteRP2350V6.04.00RC1_RM2.zip
Edited 2026-10-06 02:20 by Gerad

I will analyse this further but, for the avoidance of doubt, this is a Fritzbox specific issue or at least I'm not aware of any reports on a non-Fritzbox router.
I can type cpu restart forever on my network and it will always re-connect.
I'm unclear why the patch limits to rp2350 only as presumably the rp2040 has the same issue?

I'm having the same problem with the RP2040, which is why I'm using a “do while...” loop. Maybe it's a “Fritzbox” issue. But in Germany, that's pretty much the norm. Still, after 2–3 connection attempts, the connection is established.
Edited 2026-10-06 03:30 by Gerad

I will implement the retry code but not the soft reset change.
It isn't safe when called from an interrupt.
SoftReset() is called from the 1 ms timer callback, for the WATCHDOG timeout and the hang-detection timer (PicoMite.c:2433, PicoMite.c:2439).
cyw43_arch_deinit() must not run from an interrupt: the SDK's own check panics there (async_context_poll.c:49).
In a release build that check is off. The network stack is then shut down from inside an interrupt that may have arrived in the middle of a network call.
If that crashes, the hardware watchdog hasn't been started yet, so the board hangs instead of restarting. WATCHDOG exists to get a stuck board running again, and this would make it hang.
In any case, the driver already does this: every cyw43_arch_init() drives WL_REG_ON low for 20 ms, then high, then waits 250 ms (cyw43_bus_pio_spi.c:360).

  matherp said  

I will analyse this further but, for the avoidance of doubt, this is a Fritzbox specific issue or at least I'm not aware of any reports on a non-Fritzbox router.
I can type cpu restart forever on my network and it will always re-connect.
I'm unclear why the patch limits to rp2350 only as presumably the rp2040 has the same issue?

I have seen the same behavior as with a Fritzbox with an ESP01S module running ESP-Link acting as AP.

Peter
Of course, you're absolutely right. That was just some leftover software from when I was trying to figure out why the connection wasn't working. It's been removed in "WebMiteRP2350V6.04.00RC1_RM2_V1.uf2"
WebMiteRP2350V6.04.00RC1_RM2_V1.uf2.zip

WebMite_RP2350B_RM2_V1_Technical_Report.pdf