Nous A1T bricked :(

[lennvilardi]

Hi !
I've bought a pack of 4 Nous A1T and I wanted to put all of them up to date (bad habit).
But for one of them something went wrong.
I tried to reset it holding more than 40s the power button and unplugged it 6 time and let it plugged the 7th.
Still no led signal. So I decided to try to reflash it using a FTDI FT232. I've flashed many Sonoff with it.
The interior design has changed compared of what I've found on the internet (https://templates.blakadder.com/nous_A1.html and https://www.esphome-devices.com/devices/Nous-A1).
I've found a TX, and I think next to it RX, and the 3.3V. I've tried to put it on programming mode directly on the pin of the ESP8266EX but I'm unsuccessful.
If anyone have an idea... soldering is not very easy on this board for me so i hotglued dupond on the pads.
Is there a GPIO 0 more accessible on this board ?

[hagenbuch]

Has Tasmota been working before? Does any LED go on when plugging it in?

In order to reset Tasmota, you don't need to press any button, just

1. Unplug it for some 30 seconds.
2. Then 6 times: plug it in, wait 5 seconds, pull it out, 5 seconds..
3. Seventh time: Leave it plugged in. The accesspoint mode should start and offer you a "tasmota-something" Wifi

I bought 4 Nous A1 some months ago but their PCB is blue and looks quite different, the chip is 8285! I managed to flash them OTA with this

https://github.com/ct-Open-Source/tuya-convert

[barbudor]

Tuya convert is unlikely to work

I flashed 8 or 10 of them plus the similar gosund one
Mine are exactly as the photos on the template web site

Remember that for flashing you need

• gnd
• 3v3 from a good serial adapter, many ft are not suitable
• RX and TX
• gpio0 to gnd before resetting or powering up

By the on those photos there are obviously no RGB led (referring your other question) which would be a square part 3x3mm up to 5x5mm

[lennvilardi]

Thanks for the quick answer.
Tasmota have already been working on that plug.
No led at startup.
It's the new version A1T which bring directly a Tasmota firmware.
Are the 5 seconds wait beetween the plug and pull out mandatory ? I will close it again and try it.
I can confirm in the right of RX it's TX (you see the inscription when you lift a bit the relay).
I'll keep you posted

[lennvilardi]

Tuya convert is unlikely to work

I flashed 8 or 10 of them plus the similar gosund one Mine are exactly as the photos on the template web site

Remember that for flashing you need

* gnd

Found !

* 3v3 from a good serial adapter, many ft are not suitable

I've bought a new one but it will come in 2 months

* RX and TX

Found !

* gpio0 to gnd before resetting or powering up

Maybe it's the part I'm not good at, I use the pinout from https://tasmota.github.io/docs/Pinouts/#esp8266-and-esp8285, but with a dupond it's very hard not touching the others pins.

By the on those photos there are obviously no RGB led (referring your other question) which would be a square part 3x3mm up to 5x5mm

There is one led which is green at startup near the power button

[sfromis]

When touching gpio0 to ground directly on the ESP chip, do not worry about also touching the neighbor pin to the right. That one is perfectly safe to ground too, and does not affect flashing.

[barbudor]

The leds D1 and D4 are single color leds

A RGB led would have at leats 4 pins, whether it is an analog one (3 LEDs in signle package) or a digital one (like AP102, WS2812...).

[lennvilardi]

Thanks all for your guidance and I finally nailed it !
My solders are not my best but considering the coating and the tight place ^^
I think the power button is on GPIO 0 because when I press it, it gets directly in programming mode.

[sfromis]

The template for Nous A1T indeed indicates that the button is gpio 0, quite different from the previous Nous A1. While externally similar, internally they are unrelated devices.

[gabest11]

I have various smart plugs, now waiting for a few A1T in the mail and found this discussion in google. On the photos, the internals look exactly like my old Neo Coolcam 16a models (NAS-WR01W). I had a few where tuya convert worked and transfered the contents of the flash chip to make the others work, too. No soldering needed, only a hot air gun, a tweezer, and something that can run flashrom. Probably takes me 5 minutes to do one.

[massa007]

How did you manage to open that plug? Have exactly the same model, but I cannot figure out how to get the pcb out of the case... the transparent part which is fixed with a screw was the easy part, but now I am struggling because I cannot find any other screw or clip or whatever?

[barbudor]

There should be a screw in the earth hole

[gabest11]

I used a vice to carefully push the two pins. They are held by the plastic molding. Yea.. it wont be the same again, but the screw will hold it together. Don't forget to carefully remove the wifi antenna, I broke a few.

[massa007]

Yep - the vice worked, thanks a lot! I tried pushing by hand in the beginning but it wasn´t moving at all. I guess a hammer would have worked too if used carefully.
In my model was no screw in the earth hole @barbudor, thanks a lot anyway!

[BlackCube4]

I actually broke the wifi antenna :( what can I do about it?

[sfromis]

Depends on how exactly you broke it. It may work with a wire of the same length.

[fabianmuehlberger]

Hi, I have the same problem and currently try to flash the stock espHome on it.
I am using an FT232 Serial adapter and was able to flash other devices with it.

Would be very helpful if you could provide instructions on how you managed to make it work.
Best Fabian

[barbudor]

Unfortunately the doc doesn't have photos on the inside
I have Nous A1 from before they separated A1 and A1T which inside (and outside) are the same as my Gosund SP111 (those with the screw in the French earth hole and easy to spot flashing points on the edge of the PCB)

These Néo Coolcam from the outside more looks like the Avatto OT06 which I have in 1 sample but didn't used more than the 10 min required to flash tasmota and calibrate

[lennvilardi]

It's not the same plug see on the right side there is R8 and C5 on nas-wr01w and in the nous one there is R1, it's not the same design. I hope they are safe to us

[barbudor]

My Avatto is more or less exactly the same
I recognize the spots where I soldered the wires for the flashing
I can't tell for the rest if it's exactly the same

Your coil seems to be damaged

[lennvilardi]

It's not mine I found it on another github thread just to compare if they were identical.
They're not but I don't found any document of conformity for the nous a1t plug on their website, they only displayed a CE label which may not be true...

[sfromis]

CE is no certification, really not more than the manufacturer saying belive me, this product conforms. Hard to go after manufacturers in China in case of "differing" ideas about what conformance is.

[Fettkeewl]

Hi !
I've bought a pack of 4 Nous A1T

Hey!
Sorry for necroing this. may I ask how you opened the A1T? Screw under sticker or force the edges (glued?)
I have some coil whine id like to try and get rid of

[barbudor]

If this model doesn't have the screw in the French earth hole, you need to remove the sticker on the female side and unscrew to remove the cover
Then press firmly to disangage the male pins that will push all the block out
But don't go too fast too far or you may damage the antenna cable

[meganom]

Yes, there is a triangular screw under sticker:

And yes, there is no screw in the French earth hole. I noticed it only in A1 version.

[meganom]

Just for information. I have also a problem with this plug, described here: ascillato#595
This post helped a lot to understand where to connect serial interface.

@lennvilardi Have you faced any new problems after re-flashing via serial interface? And which serial adapter have you used, FTDI FT232? Thank you!

[Jason2866]

@meganom The issue you have linked are not related.

[Miq1]

Could someone give me a hint where to find the TX pin on the A1T? RX, 3V3 and GND are obvious, and GPIO00 is connected to the button switch - but where is TX?

[meganom]

Hi!

It is here:

Tx label is under Relais. So be careful not to damage the plastic case of the relais.

[Miq1]

The D1 and D4 pads are open - I suppose the former two red and blue LEDs were supposed to go there? Anyone tried to solder some SMD LEDs on those pads?

[thomas-lentz]

Hi,
I know I shouldn't do this, but it is the most technical thread I found to Nous A1T...
The current Nous A1T configuration (according to blakadder's template) doesn't "see" the direction of the current. If you use the Nous A1T in conjunction with a solar-inverter there is no "-" sign at the Power or the current, when you supply to the house/grid. To see if there is any software solution to this (without opening the Nous A1T), I would like to know, which power measurement chipset is used in the Nous A1T. unfortunately pictures here don't allow me to read it.
I appreciate your help!

Greetings Tom

[arendst]

Choose a SetOption as this uses less resources.

[arendst]

BTW the -i option is not meant for positive/negative measurements. It's meant for hardware designers using an inverted signal.

[barbudor]

I do agree. My suggestion was actually

• implement a SetOption to say 'energy inverted'
• remove the abs() and use the value of the setoption flag to actually change sign if set

I'm not sure we can avoid a breaking change as some hardware implementation may be correct and some not. So some will need to activate the setoption.

[thomas-lentz]

Why not make it the suggested way

Setoption<yy> [0..3]
0: "always positive" (default and also today's behaviour)
1: "always negative" (like today's behaviour with a "-" in front of it  / value multiplied by -1)
2: "direction-sensitive" (show current flow/powerconsumption as designed by the power meassurement chip producer) 
3: "direction-sensitive inverted" (the same as "2" but inverted / value multiplied by -1)

Having the "0" as the default, the behaviour would be like today - avoiding any breaking change. The "1" would be the opposite sign of today's display. "2" and "3" you choose according to your specific device ...

[Jason2866]

The + / - direction is not needed. The power drawn from the Inverter is under 1W. This device cannot measure such low loads. So every discussion needing +/- direction for connected Microinverter is an academic one.

[r10r]

Has someone of you added some additional sensors to the Nous A1T already ?
I'd like to attach one or more DS18b20 temperature sensors and/or the BME280 Environment sensor

Is it possible reuse RX / TX or the D1/D4 pad as IO pins for I2C ?
I'll update the https://devices.esphome.io/devices/Nous-A1t page if possible.

[r10r]

Thanks for your response. What pins did you use for I2C - the RX/TX pins or D1 or D4 ?

Another thing I learned, a temperature sensor is completely useless inside a closed space, the micro generates heat and it gets trapped in.

I plan to drill a little hole and attach the sensor with a wire to measure the temperature inside of the freezer.

[r10r]

@barbudor Thanks for the response - so I'll dismiss this idea.
Maybe we should add this warning to the device's page https://devices.esphome.io/devices/Nous-A1t,
because the pinout inspires people (like me) to attach sensors to it.

[gabest11]

That's a very good question, I can't remember, it was maybe a year ago. It is still wired in but not very eager to disassemble it right now :)

[r10r]

@barbudor Can you recommend a device where it is possible to attach external sensors ?

[barbudor]

It all depends which form factor you are looking for.

If it's a plug, then only ones without power measurments would most likely be safe but infortunately most are not as easy to open as the Nous A1T.

Shelly Plus 1 have connectors for external sensors: https://kb.shelly.cloud/knowledge-base/shelly-plus-1#ShellyPlus1(SNSW-001X16EU)-Addoninterface

Otherwise, for sensors build, the simplest is a NodeMCU/Mini-D1 and a USB wall adapter

[rira2005]

HI
Thanks your Solution work for me. Button GPIO0!
Used Tasmotizer to unbricking. ;-)
THX