waiting for download when I restart the board

[Asb]

Hi

Sometimes when I restart (unplug power, and back again) the board I get the following msg in repl:

rst:0x1 (POWERON_RESET),boot:0x6 (DOWNLOAD_BOOT(UART0/UART1/SDIO_REI_FEO_V2))
waiting for download

What is the cause of this? I am a bit worried as if a power outage happens when I am not around, the lopy will eventually be stuck with this msg. From what I've read this message appears when you connect P2 with GND and press reset? This is not the case for me.

Thanks.

[robert-hh]

@Asb That happens if at restart GPIO0 (P2) is at low level. Do you have anything connected to P2?

[Asb]

@robert-hh No. I have my own pcb instead of the expansion board, taking a quick look the soldering looks good (no unintentional connections). I have ~50 lopy1 on the same pcb.

This is the 2nd time I experience this, and I have restarted it more than 50 times.

[johand]

@Asb I saw this problem from time to time with a W01 module on a custom board. Adding a pull up solved the problem.

[Asb]

Thank you for the input.
I am not using any OEM module, but https://pycom.io/product/lopy4/ I would assume this already have a pull up if this can cause problems as mentioned. Not able to find any schematic and check myself.

[robert-hh]

@Asb The ESP32 has an internal pull-up at GPIO0. But that may be too soft. The LoPy4 has no additional pull-up, as far as I can tell.

[Aakash Mr]

Because this page showed up among the top results, but didn't resolve my problem, here's sharing my solution, for those who end up here looking for it -

In my case, pullup on D0 didn't work. 1k, 470e, whatever. but I had put a 10uf to ground on my esp32 reset pin (in addition to a 10k pullup). that was causing the uc to (most of the times) go into waiting for download.

upon removing the cap, it stopped going into the download by itself.

this page helped me (actually, applying the inverse logic of it): https://randomnerdtutorials.com/solved-failed-to-connect-to-esp32-timed-out-waiting-for-packet-header/

[Adam K]

Or, as in my case, the "Boot" microswitch on my dev board was broken and pulling the pin to ground.