Tasmota: Can't flash firmware on Sonoff Dual ver 2.0

[ribesx]

I tried to flash the firmware on my Sonoff Dual Version 2.0, using a FT232RL FTDI USB adapter, but I can't get it working. I checked the wirings multiple times, connecting TX to TX and RX to RX, and I tried to swap them as well. I'm connecting GPIO0 to the GND for 1/2 seconds while I connect the adapter to the USB port on my PC, but it never works. I tried flashing with Arduino IDE and PlatformIO, and I always get

error: espcomm_open failed error: espcomm_upload_mem failed error: espcomm_upload_mem failed

[edit21]

You need to go tx-rx rx-tx and I always tend to leave gpio0 shorted until I'm done.
Sounds silly but you may want to check which comm port you have configured too.
I have flashed a good few ver2.0 in the last few days - not had an issue yet :(

[ribesx]

I tried to do that, but it didn't work. I tried installing PlatformIO on Ubuntu and did the procedure but I still can't flash it. I think I'm not shorting gpio0 maybe, I'm using a jumper to connect gpio0 to the ground, as in the picture

[andyfitter]

I managed to grout GPIO via the thin trace on the other side of the board. Maybe you'll have more success there?

[ribesx]

I already tried that, I also scratched the trace a little bit in order to make a better connection, but no luck yet

[andyfitter]

When I achieved it via the top track I grounded it from before, to about a second after power was applied. I believe you can tell it has worked when the LED doesn't flash at all. If its flashing in any pattern I don't think you've taken it into Flash mode.

[ribesx]

So I guess that’s my problem, when I connect the adapter to the USB port there’s always the blue light flashing on the sonoff dual

[Norien]

Sonoff dual was a huge pain for me. Must have had 20 bad flashes and was getting real frustrated. Tried a new ftdi and it worked first try...

[ribesx]

I ended up burning my sonoff, I ordered a new one, and I’ll try another ftdi as well.. It’s really frustrating

[chris-thorn]

I know it's an old thread, but I found I'd got a couple of apparently dead Sonoff Basic modules (6+ months old) and three brand new ones (1-2 months old), and I couldn't get any of them to flash using my PL2303 serial adapter:

I just kept getting the same error:

error: espcomm_open failed
error: espcomm_upload_mem failed

I've flashed plenty of Sonoffs in the past using that adapter, but it appeared to have just stopped working. I tried:

• different methods of powering on the board to get it into flash mode
• swapping TX and RX
• reinstalling the serial adapter drivers
• trying a different PC

... but nothing worked.

However, I bought a CP2102 serial adapter like this one:

... and I'm able to flash my new and my old Sonoffs with no issues at all!

Chris

[tyriis]

I hold the jumper against the gpio pin from the esp8285 Chip, it finally worked after 20 failed tries with the position shown.

[b-runden]

Hi all,
I've also spent days on that "§$%ing sonoff dual v2.0. It wont start flashing mode without having GPIO0 -> GND.
Neither the button nor the PINS on the board for for GPIO 0 are working in the beginning. (Needs programming first, I guess. It seems to be a specialty for the "ESP8266ex" (likely not the 'pure' 8266...).
Like @tyriis I connected GND (of one GND pin on the main side) to the resistor's end on the pic of @ribesx ' post.
that finally worked. (no scratching needed, just pressing a jumper pin to the resistor. (whole time of flashing. Otherwise flashing may stop/break.)

I also tried sonota, however that didn't work either, maybe because I did already the APP Provisioning with iTead... Didn't spend any resource anymore. Flashing with usb serial is pretty fine.

BTW: Makes no difference if provisioned with iTead's App or not...

[calcipher49]

I tried to flash my first Sonoff Dual R2 today. But seems impossible to start it into flash mode. 2 hours of multiple failures...
Solved using Sonota and OTA flashing, works like a charm.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale[bot]]

This issue will be auto-closed because there hasn't been any activity for a few months. Feel free to open a new one if you still experience this problem.