Everything works except the serial comms

[domwells27-a11y]

Hi all,

I have built all my modules, and am just starting to configure each one. However, I cannot get the web interface to send messages to any of the units. Here's what works:

• Each unit successfully calibrates on start up
• EEPROM setting has been set for each unit
• ESP web interface loads correctly, and I can access via IP address
• Serial debug on Arduinos and ESP are reporting back in serial monitor.

Here's what I have done:

• Ensured the Arduinos and ESP are not in serial debug mode
• Confirmed the number of units matches the ESP program
• Confirmed the DIP switches are set correctly
• Tried another ESP, same result
• Tried multiple Arduinos (albeit from the same batch), incase there is an I2C issue
• Tried 'sniffing' the I2C bus with a logic analyzer. I get signal immediately on power up of the ESP, but then silence after, and from what I can tell lots of NACK codes, no ACK.
• Altered the code as here (ESP8226 no connection to Arduino Nano #31 (comment)). It didn't make a difference.

A couple of questions:

What is the expected behaviour when using a logic analyzer? Should I expect a constant stream of data if the ESP is set to 'clock mode' for example?
Anything else I have missed? Could the PCB be defective (assembled by PCBWay)?

Many thanks
Dom

[JonnyBooker]

Hello there and apologies for the late reply, I haven't had the time or capacity to look at this project in a while.

Everything you are doing would suggest things should be working. I'll be honest in that I have no idea what a logic analyzer would say I have not used one before.

I have seen in the past that the specific ESP was a problem for someone else, I was told they had also tried several ESPs however none of them worked. They had ordered from AliExpress and none of them worked properly. There are also variations with ESP01 and ESP01S, personally I used a S variation and they used a none S but off Amazon instead and it worked.

It was this one I used:
https://www.amazon.co.uk/dp/B01LK83TX0

I don't think PCBWay would have gotten it wrong, I've heard them work from several different users. If you could rotate the boards or install the ESP in another I would try that.

I apologise I don't think I've been too useful, everything sounds like you are doing it right here. I would try focus on getting the web interface with 1 unit and programming in 1 flap to be used to see if can get that working, try isolate the problem.

If I can provide anything else more then happy to but not sure what else to provide, apologies! Hopefully might have progress by time see this

[domwells27-a11y]

Thanks for the response! A small update, I purchased the AZDelivery ESP from Amazon as suggested, but still get no I2C comms. That's 3 separate ESPs from separate manufacturers tested now, so I cannot see this being the cause. I have a spare pre-soldered board from PCBWay with the 3.3V components, that I will try using as the master. I'll leave an update.

I wonder if I could send an I2C command from another Arduino to see if the Unit Arduino is receiving I2C? I'm not particularly savvy with Arduinos so if someone can point me in the direction of an Arduino sketch to trial I'd appreciate it.

EDIT - I've managed to replicate the ESP data transmission using another Arduino plugged directly into the SCL and SDA lines. The unit responds correctly and steps to the correct flap. So the Arduino is receiving I2C correctly. I can only assume there is an issue on the PCB between the ESP and Arduino (Q1,Q2 and R1-4)

[JonnyBooker]

Thanks for the response! A small update, I purchased the AZDelivery ESP from Amazon as suggested, but still get no I2C comms. That's 3 separate ESPs from separate manufacturers tested now, so I cannot see this being the cause. I have a spare pre-soldered board from PCBWay with the 3.3V components, that I will try using as the master. I'll leave an update.

I wonder if I could send an I2C command from another Arduino to see if the Unit Arduino is receiving I2C? I'm not particularly savvy with Arduinos so if someone can point me in the direction of an Arduino sketch to trial I'd appreciate it.

EDIT - I've managed to replicate the ESP data transmission using another Arduino plugged directly into the SCL and SDA lines. The unit responds correctly and steps to the correct flap. So the Arduino is receiving I2C correctly. I can only assume there is an issue on the PCB between the ESP and Arduino (Q1,Q2 and R1-4)

Sorry to hear the ESP didn't work from Amazon!

I think you've gone into this far beyond my comprehension if I'm honest. I have heavily relied on the efforts of David's (the original creator) PCB design and don't have much knowledge in the area of PCB's etc, I am better at the software side of things! I applaud you for your efforts and discoveries!

Its very interesting findings, my first thought was could you maybe test the lines between the ESP and Arduino for continuity but not sure that is going to be possible as its a multi layer board. Something haven't mentioned above is if you've managed to test multiple boards with the ESP at all? When I went with PCB Way, I remember I actually got a bad Arduino board on one where one was actually fried after powering it up which rendered the whole board useless so just wondering if had bad lines on one board.

I don't know if it would be at all helpful but I'm happy to try dig out my BoM with part numbers to see if anything else could be amiss there potentially between what I used and what you got too?

I am just throwing all the options I can here admittedly, apologies if they aren't helpful or if have already tried and tested them. I'll keep suggesting if think of anything and try keep replying if have anything.

[domwells27-a11y]

@JonnyBooker thanks for your help. I will build up another ESP board, just waiting on some PCB headers that I am missing. If that doesn't work I may ask over on David's site