ESP8266 (NoceMCU), EPEver Tracer A and MAX485 module

I’m guessing that this is to do with the fact that you aren’t using a proper FTDI and that you aren’t getting a proper power/ground supply to the TTL/USB adapter when not powering it from the PC.

However, your screenshot shows a baud rate of 9600 but my code uses 74880 for the serial monitor.

Sometimes. It requires the output of the Tracer to be set to a certain setting, and these aren’t very intuitive.
As you’ll see from my PCB, I’ve started using a 2-way relay board that is connected to D6 and D7, so I mostly use that approach now.

Glad you’ve had some success anyway!


It can be, but the GND pin is common for the Wemos, Tracer, and TTL/USB adapter - all of them are interconnected.
Do you think it will work when I will be just sending data to Blynk and ThinkSpeak?

Yes, because the software I was using support communication up to 57600. Of course, to make it work, I reduced the baud rate of the Serial1 in the code to 9600.

So you control the load ON/OFF state via a relay and not by the device itself?

Yes, I expect it will.

Either approach works. I have two of these devices, one at home and one in Spain. The one in Spain was running on my original hardware and although I recently upgraded to my new PCB, I’ve not yet swapped over to using the relays to control the load power, as I need to make some changes to my load wiring first.


Hello Pete,
Just to let you know - I implemented the ThingSpeak and Blynk with your code and everything is working fine (when connected to an external power source).
When I try to get the Wemos powered directly from PIN 1 (orange) and GND (brown), the board got powered (I can see the onboard LED is on) but it doesn’t really work.
I really don’t understand the reason why it won’t work, I tried to connect directly to VIN and GND and also by attaching the wires to the power inlet jumper - neither way works.

Best regards, Paolo

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