How to flash LN882H with open source Tasmota/Esphome style firmware - backup procedure included

try doing the same but put the tool on the D partition, or any other partition outside C

>>20955951

I think I saw this a few times and switched from fake FTDI to CH340 USB TTL. can't quite remember. do you have other USB-TTLs to try?

We've had already multiple reports on our forum saying that not all USB to UART converters are reliable and functional for flashing. Try using another converter.

But with my USB to TTL I can do DUMP

Do you think you can't write in the same way?

Hi all

Thanks for you effort on the LN882H.

Same situation here The Rx/Tx LED on my FTDI USB-to-Serial start blinking.
But after a few seconds the LN882H_CMD_Tool retuns a fail.

C:\Users\xxxxx\Downloads\LN882H_CMD_TOOL>LN882H_CMD_Tool.exe COM10 download flash 2000000 0x0 OpenLN882H_1.17.457.bin
Fail. Error downloading file.

I use the 3,3V of the USB-to-Serial as power supply for the LN822H Module

Both of you seem to have a different USB to UART converter than I have.


On this converter, I always use a jumper to connect VDD to 3.3V, because on this converter it is required to select 3.3V voltage levels.

@p.kaczmarek2 I'm using the same USB to TTL converter that you showed, and I get the same error.

I'm starting to think it must be software related in some way, cause If i try to send the flash command with a random name for a .bin file that doesn't exist I still get the "Fail. Error downloading file"

Are you using Windows 10?

Yes, I'm using windows 10.
And I've also tried using another PC with win10 for the flash procedure, with no luck.

Well, either you're doing something incorrectly, or your LN882H may be not flashable - but I think it should be flashable. Anyway, maybe you can just consider shipping it to me in a letter so I can check on my side?
I am really running out of ideas.
To be clear, you're flashing it outside the circuit?

Hi,

maybe to compare the settings we have:

Win11 PC. LN882N Module is labeled "LN-02" it is desoldered from a Mini Smart Switch "RMW002". The chip is labeld:

LIGHTNING
LN882HKI
749AY T16
AAB M 2223

I am using a USB to Serial with "FT232RL" chip. For VCC I select 3,3V with jumper.
But a also tried to power the LN882N Module with a 3,3V lab supply to ensure sufficent peak power supply.
Full power cycle before each programming attempt.

If I execute:
.\LN882H_CMD_Tool.exe COM10 download flash 2000000 0x0 OpenLN882H_1.17.457.bin
Rx/Tx LED on the USB-to-Serial blink for 2...3 seconds, some action happening... But the return is "Fail. Error downloading file."

If I execute:
.\LN882H_CMD_Tool.exe COM10 download flash 2000000 0x0 test.bin
And "test.bin" file isn't even existing, the tool still returns: "Fail. Error downloading file."

If I remove TX-Pin, the LN882H_CMD_Tool is returning "Fail. Could not go in download mode.". --> Different error message, so I suspect the bootloading process is starting in my setup but then aborts.

That is the one I have flashed for upcoming YT video:

this is my USB to TTL
https://mauser.pt/catalog/product_info.php?products_id=096-7520

Google Translate description
"The USB-Serial TTL Converter PL2303 is an adapter that uses the Prolific PL2303HX chip to convert USB signals into TTL RS232 signals, which makes it extremely useful when you want to communicate between the computer and microcontrollers in general. The USB-Serial TTL Converter PL2303 is a board with reduced dimensions that has at one end a USB connector to be connected directly to the computer and at the other end a pin bar for easy connection with the board whose communication will be established, has voltages 3.3 and 5V, which allows you to work with a greater number of microcontrollers regardless of their power supply.

For correct operation, the USB-Serial TTL PL2303 driver must be installed.

Main features:
- Dimensions: 50x15x7mm;
- USB 2.0;
- Standard USB type A male;
- TTL output 5-pin connector (5V, 3V3, TXD, RXD and GND);"

tried with AV disabled?

Hi,

I was the same problem. ("Fail. Error downloading file." )
I chose downlad speed end the flash is OK!
Try this:
LN882H_CMD_Tool.exe COM7 download flash 115200 0x0 OpenLN882H_1.17.456.bin

(I used cp2101 because faster than PL2303 )

Best regards!

I'll try it soon!

I tried using a Win11 pc, with no luck.
I already tried changing the baudrate to 115200, but I still get the same damn error.
And yes, I'm trying to flash the module while is desoldered from the board.

(Also tried putting the tool folder in the D:\ partition, same error appears)

Maybe try 57600 or 19200?

D:\LN882H_CMD_TOOL>LN882H_CMD_Tool COM21 download flash 115200 0x0 OpenLN882H_1.17.457.bin
Ok.
D:\LN882H_CMD_TOOL>

I got it, thank you. finally
it had to be on disk D and with a speed of 115200

so it was not working on C drive, even with correct baud?

Hi all,
I am new here.
I can confirm that LN882H can be flashed with NODE-MCU (esp8266) with CH340.

Success!

I had to switch to a USB to Serial with a CH430 chip (FTDI was not working for me). I also reduced the baud rate to 115200 while downloading.

I have tried everything, but I can't get pass this error.
This is really pissing me off, I think I will throw this damn chip in the garbage and replace it with a TYWE2.

>>20958708
Work on c:
the problem is correct baud 115200

dullu wrote:

Having such a long wires is bad practice, you should really shorten them. I already have seen many cases where just the length of the wires were breaking up the flashing. The first rule of good flashing setup is to keep wires short.

Yes, you are 100% right!!
Yesterday, I flashed it and it was working everything fine.
and almost all function was working...only thing I noticed is ..... when I assign static IP and reboot, it will again come up with DHCP only.
tried many times (assigned all like IP, Mask, GW, DNS) but it is not saved.
Also, while applying with template for smart switch, it says Bad command ? "lfs_format" comand not found!!

Anyways, I burned the LN822H last night because of loose long boot wire was by mistakenly touched somewhere in ESP baseboard connectors
and I got some bad smell from the board and now no WiFi, no activities at all.

Soooo... even I have flashed with long wires successfully, it is bad practice for other things too (like frying your chip).

Now I am waiting for another from aliexpress.

Thank you all for such a wonderful guidance.

I have a problem, I derived the MAC address
But when I change the Mac it doesn't connect to my home WiFi
I have to write the dump again, flash with new bin and try to configure it again. unsuccessful

divadiow wrote:

I ripped the pad off boot on my first LN-02 mini switch not moving it around delicately enough 😳

ive gone back to this. desoldered from PCB and examined trace from where boot pad was. Scratched off the ink along the T in TX text to reveal the copper trace. Fluxed and tinned a little, then used pogo pins to ground boot. LN-02 now flashed to OpenBK.

Also. I used fake FTDI USB adaptor, so didn't have to use CH340 as previously thought. Flashed without setting baud in cmd

no one else had problems with mac address?

voodoopt wrote:

no one else had problems with mac address?

I have not. I've flashed 3 or 4 units now.