Sonoff basic: flashing works fine (no error), but no serial output or any other sign of life

[tr1plus]

Hello

I got my sonoff today and tried it out. The default firmware worked fine so I know the sonoff is (was) working.
Next step was to flash tasmota firmware. I got the latest version and followed all the steps. Flashing went fine. I reassembled everything, connected it to power and... nothing.
I spent a while looking trough the issues: #611 seems to be relevant but the solution is either not very clear or doesn't work for me.

What I've tried:

• Setting the flash mode to dout
• switching tx and rx on my adapter
• flashing with the button held in
• holding the button for 4 seconds when connected to the adapter

Nothing seems to be working. I don't think I broke my sonoff (yet) as I'm still able to flash.

I am using arduinoIDE

Any solution/insight in this problem?

Thanks and kind regards
Joren

[ionciubotaru]

1.check the arduino serial window parameters in the right lower corner
2.use putty to open you serial port at speed 115200

[tr1plus]

baud rate is the same as the upload speed
I'm not home right now, but would putty show anything else as the arduinoIDE serial console? My Sonoff doesn't even blink the LED or anything so I'm thinking there is more to it?

I spent yesterday night reading and it seems maybe a new sonoff version was released which doesn't work with custom firmware?

[ionciubotaru]

All sonoffs are based on esp8266 so Tasmota will work as fine as the original firmware.
Try this:

• connect serial ftdi
• press gpio0
• remove and reconnect power to sonoff (keep ftdi connected to computer, remove power line between ftdi and sonoff) - keep gpio0 pressed during this process

If you see some garbage on the serial (try putty) is ok.
If not, you have a problem with serial, ftdi, etc.

[tr1plus]

just for my information. To get serial output, do I need to keep tx/rx connected and connect the main power. Or only power in via the FTDI? I read that it should only be FTDI right and I should never connect mains and ftdi at the same time?

I will try flashing an older verion of tasmota tonight. I read in another issue that was the solution for someone. Maybe the new sonoff basic is not compatible after all: #608, #463 (read more down in the issue)

Thanks for helping already

[ionciubotaru]

power sonoff via ftdi during debugging or flushing
do not connect mains and ftdi in the same time

[ionciubotaru]

I received 10 sonoffs basic and few sonoffs touch last week from banggood.com - is cheaper than itead :) -and I was able to write all of them. Entering boot mode by pressing gpio0 at startup is hardware encoded in esp8266 so itead cannot change this behavoiur

[tr1plus]

I also got mine from banggood. I'll test again tonight but I have followed all those procedures.

What version did you use to flash?

Thanks

[ionciubotaru]

arduino 1.8.1
esp8266 for arduino v2.3..0
Tasmota 5.3.0

[tr1plus]

Ok, i'll verify the versions tonight.
One additional question, I also heard not all FTDI adapters are good. I got the following one from banggood: https://www.banggood.com/FT232RL-FTDI-USB-To-TTL-Serial-Converter-Adapter-Module-For-Arduino-p-917226.html?rmmds=myorder

Would this one be good or should I get a more trustworthy one?

[ionciubotaru]

I use FOCA for more than 5 years and works perfect
try to decrease the upload speed, maybe 115200 is too much for your ftdi chip

[tr1plus]

Ok, so I followed your instructions step by step (using same versions as you) and I got weird characters in console... I guess that's a good start.

Connecting the sonoff to main power again does nothing. No LED, button does nothing... I honestly have no clue anymore :(
http://imgur.com/a/9TLFK <-- output of console + serial gibrish

Thanks for helping, but I'm at a loss :(

[tr1plus]

Ok, I also just realised I was using 5v, my FTDI connector has a weird thing you have to swap from one side to the other.
I'm not sure if I damaged anything. I still got serial output so I guess it is not a real problem?

[tr1plus]

tested with some other firmware (https://github.com/KmanOz/Sonoff-HomeAssistant)
Same results; I get weird characters in serial console, but once I plug it in no response at all.
Seems I am only able to flash when I put the connector on 5v, 3.3v doesn't even allow me to flash.

Is my sonoff just broken?

[davidelang]

feeding the esp8266 5v _will_ fry it, so if you've tried to boot it at 5v, I expect it's dead. k

[tr1plus]

but I still get serial gibrish, so that tells me it (may be) is alive? or am I mistaken there?