💬 Easy/Newbie PCB for MySensors

[dbemowsk]

@sundberg84 That's why I wanted him to send pictures. There are a number of variables that need to be in place depending on the configuration that you are using with this board. Is he using a 3.3 or 5 volt arduino, does he have a regulator, are the correct jumpers in place. Any one of these missing factors can make it not work.

[akamap]

EDIT : Seeing the pictures this big, I think I know why and it is my fault. I tried to save energy by desoldering the led on the arduino. I followed a post here on mysensors.org. But I just realized I might have desoldered the wrong thing on this arduino. I'm not sure what I desoldered, but it might be what is causing the problems (I desoldered the tiny thing below the led) I'll put a fresh one to see if this is working.

Thanks

Original response :

Ok, thank for all the answers and here is more information.

I power it via 2AA battery. I did put a jumper on the battery point. And I am using a pro mini 3.3v (Cheap chinese clone). I am using a step up regulator to step it up to 3.3v for the arduino.

I measured the voltages and they are as follow :

Without USB programmer (Not working) :
Battery : 3.00V
Input step up : 3.00V
Output Step UP : 3.35V
VCC and GND on arduino : 3.34V
VCC and GND on Radio : 3.01V

With the USB programmer pluggued in (Working) :
Battery : 3.00V
Input step up : 3.00V
Output Step UP : 3.47V
VCC and GND on arduino : 3.48V
VCC and GND on Radio : 3.00V

Another information, I did not solder directly the arduino pro mini (you will see on the pictures). I don't know what the are called but I'll call them "extender". I use them so I can unplug the arduino in case I fried the pro mini.

Here are some pictures with and without the usb programmer plugged in :

[sundberg84]

@akamap thats just the resistor... should not be the problem.
I cant see anything obvious. I have some radios without silkscreen and they work....... like a clone. Not the best but most work ok. Try adding a capacitor on the booster - might be a noisy one... I would recommend to try a 0,1uF ceramic if you have. Otherwise just wack in what you have... not to big i think.

If you power it from the booster/bat you cant power it the same time from USB! Disconnect VCC from the ftdi adapter.
Connet RX/TX and GND to begin with. RST if you need to upload. Two power sources makes one to much.

[gohan]

@akamap remember also the cap on the battery measurement side if you want to get good readings. If you want to use batteries you need to remove the voltage regulator from the pro mini, once you done your troubleshooting

[akamap]

Thank you everyone. Everythings seems to be working now. I did solder a capacitor on the booster.

But I don't think this was all that was bad. I also find out that when I touched the capacitor for the radio, I was having mixed result. So I soldered the capacitor directly on the radio.

Now, everything works fine. I guess I burned the trace or something was creating a short with this part.

I just need to remove the voltage regulator as suggested by gohan now and I can start testing my battery life.

Thanks again. Great library, great forum but most of all, great community.

[sundberg84]

So its coming up for a new revision of the EasyPCB (both Nrf + RFM edition).
I have had some suggestions from the community so far and some thoughs of myself:

• ATSHA204A (signing)
• Change 0,1uF and 10uF capacitor so now 10uF is on the input and 0,1uF on the output
• Line up MysX connector for a more clean placement of daugherboards.

Anyone have any other input before i start the work?
I will not take any suggestions that will make the board heavy or non user-friendly. Still the same goal - only easy to use components, easy to assemble and easy to understand.

[gohan]

How about a flash chip + 2 resistors for FOTA ? :innocent:

[sundberg84]

@gohan - interesting. What would be the easiest way to do this do you think? Placement?
Can I avoid SMD components?

[gohan]

the flash chip is 8 pins smd unless you choose a specific breakout board, resistors are your choice; they could fit unterneath the pro mini or on the back side

Also you may need to work on the NRF5x version too :D

[mickecarlsson]

Put the battery measurement components under the Arduino. This makes the board more generic and frees up space on the right side of the board that can be used for more sensors. Expand the prototype area so that more sensors can be installed on the board.
And if one uses the board for battery only, the whole right section can be cut off but the battery measurement circuit is still there.

[mickecarlsson]

Now that I think of it, there is a small difference between the NRF and RFM board, the prototype area on the RFM board is not correctly spaced, the holes are a fraction to narrow spaced, one cant fit a header there without bending the pins

[gohan]

@mickecarlsson said in 💬 Easy/Newbie PCB for MySensors:

Now that I think of it, there is a small difference between the NRF and RFM board, the prototype area on the RFM board is not correctly spaced, the holes are a fraction to narrow spaced, one cant fit a header there without bending the pins

Yes, I noticed that too

[sundberg84]

@gohan @mickecarlsson
Thanks for your input! I will probably redo the Nrf version in KiCad since the old in is in eagle so I will line everything up :)

About the battery measurement components under the Arduino - I was thinking of putting the signing chip there.
If you want to use the battery divider you need the booster as well so therefore its nessecary to have the board uncut. with this in mind I think it does not matter about the voltage divider placement or?

Im not sure a 8 pin SMD component is right for EasyPCB - It seems a bit to advanced and unclear?
Maybe I can do this with a MysX shield?

[mickecarlsson]

If I don’t use the booster and connect both BAT and REG and feed the board with two AA batteries i can use the battery components to measure the voltage of the battery. That is how I use it today.

[sundberg84]

@mickecarlsson - ahh, I see - good one!
Let me think and maybe try some in KiCad and i let you know what I descide.

[gohan]

The flash chip uses pins that are not on the connector.
I understand that you want to keep it simple, but adding the signing chip and the flash chip to a project it is not very easy either

[sundberg84]

@gohan - you are right.
Maybe I can use the back side for the smd parts? Again I will test and see how it works out in KiCad. I might do some testing and post to get feedback. Im really afraid I will lose the easy to use function which the pcb is designed for though and if I feel I do the smd parts will be excluded.

Maybe I could do a rev 10 which includes more heavy stuff and keep rev 9 as well as the Easy version.

[gohan]

I don't see it as a complicated thing, since if you don't need it then you just don't use it and you only have a few smd pads unused.

[sundberg84]

@gohan - valid point!
What makes it complicated is if you are a new user who sees all these pads and dont understand if they have to be populated or used. But by adding those with clear labels on the bottom side might do the trick.

[gohan]

@sundberg84 Exactly, maybe a label like "signing" and "FOTA" would make it more obvious to the user (of course it needs to be added to the project page too)