3510

got my esp32 devkitc from china
it seems i am very unlucky this one does not work too
no modules found no testcode work
have tryed new firmware(25) and from other computer

i made a putty screenshot on testcode
test2

3511

That output looks like it is reporting an invalid application image. Perhaps try and erase the flash and try again?

3512

disconnected again from pcb and flashed test code
same putty output - invalid header

i dont know what else to do
this is crazy

have ordered 2 new esp from other seller, this is insane.

flash
flash735×791 34.8 KB

3513

Just to be safe, try flashing one of the older releases, just in case a problem has crept into the new build process on GitHub.

3514

where can i get the oldest controller test file for flashing with node mcu flasher?

3515

They are all on GitHub, in the release section

3516

the controller test file is only available since 3-17 release

3517

Hey Stuart, there are lcd touch panel displays available with an sd card slot on them, will that work if I just remove the card slot on the board?

3518

No need to remove the card slot on the board, just don’t use both at the same time

3519

Sorry didn’t realize you were using the test file.

That file cannot be programmed using nodemcu flash tool, the file is not the correct format.

Can you use the real controller code without problem?

1 Like
3520

Stuart
2 of my 4 test v4.21 modules are not working,
i tried this with the new arived v4.4 modules and they worked on first try with old and new firmwares

have soldered the attinys exactly the same on 4.4 and 4.21 modules
maybe some bad solder on attiny il check this

3521

How did you program them? Suspect it’s the fuse settings.

1 Like
3522

programed them over the internal AVR programmer
mangaed them all to work i soldered the attinys with solderpaste but a tiny amount has not melted
was hard to see behind the legs so i thik it caused some sort of short between some legs.
so thank you for your help.

additional question is ist possible to adjust the load resistance in module settings?
i had to change the original resistors to 5R90 because the other were not in stock
so i need to adjust to 4.72ohms if its necessary?

thanks

3523

You can only do this by recompiling the firmware, and programming manually.

Let me know if you want to go down this route.

1 Like
3524

oh no thats to complicated for me
i leave it as a indicator if some cell is bad i wil see that one is balancing more than the other

3525

test setup is working now :slight_smile:

diybmstest1
diybmstest12284×1284 468 KB

diybmstest2
diybmstest21766×802 129 KB

1 Like
3526

Hello,
I have search in github a readme file providing the meanings and troubleshooting of OOS errors, CRC errors and all the info in the homepage that gives information of voltage, send packets etc. I found in this thread that CRC errors was related to the power source giving to the controller of at least 2amps. The rest of the error code can’t find info.
Thanks in advance for any help.

3527

There are only 2 types of communication errors.

CRC errors relate to corrupted data caused by interference.

out of sequence OOS errors mean a packet of data was lost/never received by the controller.

Either way, they are both normally caused by not using twisted cables or having the cables too long and near the AC inverter etc.

2 Likes
3528

Excellent! Thanks for your help and keep up with this incredible project Stuart.

3529

@Malloween
I’m not exactly sure what you are asking.

The dump load of the module 4.21 is 0.8A, and the 4.40 about 1.2A without heatsink.
The dump is limited via temperature sensor.
With efficient cooling, it will be roughly 50% more.
That is per module, connected to one or more (parallel) cells.
This should be enough when you top balance the battery pack, unless the cells are badly unbalanced.

If you charge with 10A, and one cell is 99% charged where the rest is 85-90%, then the charging continues at 10A.
Result
 you need to discharge that one cell with 10A to have the other cells catch up.

With large imbalance, I suggest to use 50watt resistor and place that on the too high charged cell during this phase.
Once all cells are around the same level, 96-99%, the 0.8A is more then enough to balance, as the charge will change from Constant Current to Constant Voltage, so your charging amperage will drop to almost nothing, topping the last few %
Daly BMS uses just 80mA (0.08A), what is sufficient if you top balance most charge cycles.

Examples on how to calculate?
Google ohms law.

The part list can be found at GitHub.

Probably not the direct answer you hoped for, but the best, as you get to educate yourself on how to make these calculations.
Important to be able to understand what the numbers mean, and how it will reflect you your own installation!

I do hope this helps you enough to get the correct direction to find the answers you seek.

2 Likes