Batch of 5X ESP-01S won't boot

[kwiley]

I just bought five ESP-01S boards in a batch, so they're all identical. esptool had no trouble erasing them or writing firmware to them, but when I restart them in UART mode, all I get is the usual single brief LED wink. No terminal REPL and no MicroPythonXXX wifi network. These are 1MB boards. I have a 4MB ESP-01S that I bought last year, so it is completely different construction in terms of production runs, etc...plus the additional storage it has. I have used that board without trouble all this time and I confirmed that it is working now, in the midst of these five new dead boards, so the problem isn't my USB/ESP converter. I even rewrote the firmware on the old board to confirm that the exact same firmware was used, and it works just fine.

I realize there are two versions of the firmware, a 512KB and a 1MB version. Even though my new boards have much less storage, they ought to be hold the 1MB version. But I attempted the 512KB firmware just to see if that would make the difference. I'm not sure the ways in which the 512KB version is diminished. For example, I'm not sure if I should expect to get a wifi network or if the 512KB version doesn't create one...but I don't get a REPL either, so clearly that can't be right.

I tried one older version of the firmware with no improvement.

I tried setting the flash to DIO mode. No change.

I tried telling esptool to use slower baud rates even though it never reported any comms errors during erasing or programming the boards. No change.

It can't be a bad single board, since all five are identically bad (also identically good: esptool has no trouble, and they appear as serial devices in my /dev/, but identically bad: no wifi network and no REPL), so they are systemically bad. I don't know how to interpret that.

Any thoughts?

Thanks.

[kevinkk525]

Try flashing like this:

Code: Select all

esptool.py --port /dev/ttyS3 --baud 115200 write_flash --flash_size=1MB -fm dout 0x0 /home/kevin/micropython/ports/esp8266/build-GENERIC/firmware-combined.bin

Had a similar problem with 1MB sonoff devices.

[kwiley]

IT WORKED!

Your command differed from mine in two ways. It explicitly stated the firmware size and it indicated a different firmware mode. So I tried it again, reverting each of those parts to my original command, and the part that is relevant is the -fm change. I can still use --flash_size=detect and it'll work. It's the -fm dout that makes it suddenly work.

Based on this webpage (https://github.com/espressif/esptool/wi ... lash-Modes) dout is the lamest of the possible firmware modes, as opposed to the preferable default of qio. Sigh.

Thanks again.

[kevinkk525]

Glad it worked!
Lost many days with that problem too, wasn't fun