This is simply a number change. The i2c address is different for these chips. Think there are comments in the controller code about this already.
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Cheers thanks Stuart !!
Hi, yes Stuart is right the code does mention the address is different.
I just added a new line so that it is easily changed.
In Main.cpp, search for PCF8574P and you’ll find it:
//PCF857x pcf8574 (0x38, &Wire) ; //For AT version
PCF857x pcf8574 (0x20, &Wire) ; //For T version
Thus i can easily change back if i order the AT version in future.
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So, for the less experienced, what way are the led diodes oriented on the board? Cathode on the silkskreen D side or… ?
Okay, “D3” is on negative side, “D4” is on positive side, “D2” is on negative side… something to imporve for future maybe 
PS. Can somebody please link or name what is the remote temperature sensor that can be plugged into the 5pin sensor input? I’ve used dallas sensors with 3 legs and looked through the v4 github info but I cant figure out what kind of temp sensor should/could be used there? “remote temp input 47k @ 25oC” is too little information for me, i’m sorry!
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It is a thermistor - a temperature-dependent resistor, that’s saying at 25 °C, the resistance is 47 kΩ. IIRC, there are a few comments about it in the other thread.
But those thermistors only have two pins… but the sensor header has five, so between what pins it is ment to go, and why is there five? Maybe @stuart can educate us (me) a bit on that?
Just for expansion - you only need pins 1 and 2 for the thermistor. You can use the same one you used on the module board (just put it on a bit of veroboard and solder some wires to it)
D2 is optional - however the silkscreen should still show the correct orientation.
It looks like LCSC have discontinued the thermistor that I specified in the original BOM.
LCSC.Part #: C95969
Mfr.Part #: SDNT2012X473F4150FTF
Manufacturer: Sunlord
Package: 0805
Description: NTC Thermistors 1/5W 47KOhms ±1% 4150K 0805 RoHS
A similar replacement would be
However this is a 4050K instead of a 4150K part - this is a simple configuration change in the web interface to DIYBMSv4.
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Do I have an old pcb or what is the orientation indicator? Sorry if it’s something common for such thing, googling about it showd indicators like K or A or + or - to be expected.
Ah, the marks are on the silkscreen but that seems to be covered over by the solder mask.
D2, D3 and D4 the negative terminal is consistantly on the left.
Yes. Same with the PCB’s I received. Best way to assemble I found was using the interactive HTML BoM. For those who don’t have the Kicad plug in , Marius_r has uploaded the HTML’s above (1st of July)
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Hullo! Made a little video for my kind of nubs for how to solder and program the boards easily, thanks to stuarts binary files - a big barrier of entry is now gone!
Hope it helps someone 
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Looks like no menu option to change wifi network after initial pick, in the premade binary image. You do have the menu for choosing one, as seen in the initial setup, maybe could have an option added for this in the settings menu?
Hello Antel, I use the MQTT Explore program, the web diybms integration I enable MQTT on server the ip is 127.0.0.1 localhost, then I use the Mosquitto Broker I create a subscription with the topic diybms / # the problem is that I don’t receive data in mqtt explorer with the topic diybms, do we have to make any special configuration?
Hello Sinusoidal, welcome to the OEM forums.
In case you were wondering why your post didn’t appear, it is because the system thought you were a Spambot: “New user typed their first post suspiciously fast, suspected bot or spammer behavior.” It’s perfectly OK to use the editor that’s built in to the system here, it usually even remembers how far you got if you shut down and restart your computer. I recommend that to avoid problems, you don’t compose your posts beforehand and then paste them in.
Everything looks ok, I connect to the DIY BMS access point but I don’t know what’s the default IP to access the stats page. I put on the Wemos the bin file uploaded by Stuart.
http://192.168.4.1
Edit - changed formatting to prevent text appearing as a link. BT, Moderator
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Thank you, Stuart! Really accurate voltage readings and is “eating” just around 0,68mA and up to 4mA when the LED is flashing. Now I need to find an easy way to read the data remotely, anyone can make a small tutorial on how to do that?
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