"Couldn't find RTC"

Projects Networking, Protocols, and Devices
1

I can't seem to make the RTC DS3231 work.

SDA => A4
SCL => A5

I tried the I2C scanner and it didn't detect the RTC, although my RTC lights up. I tested the A4 and A5 pins, I wired some buttons to it and it worked, the serial monitor shows it when It's being pressed. I'm pretty sure I download the right and needed libraries, it lights up but it can't seem to be detected.

So I bought a new Arduino uno r3 board, which didn't solve anything at all. Maybe it's the RTC itself, so I bought a new one and heck it still won't work.

I've searched couple of solutions online and I've tried everything that I saw, but it just won't work.

2

So it just doesn't work. Anyone who believes they have successfully got a DS3231 to work with an Arduino (including myself) must have been hallucinating, right?

3

I've been dying to make this thing work

4

Don't try and move on until the scanner can detect the RTC

The first thing to check is that you have A$ and A5 connected the right way round to the RTC. Disconnect everything from the Uno, connect the RTC to A4 and A5 and run the scanner. If no device is detected then swap the connections to A4 and A5 even though you are sure that they are correct. Run the scanner again. Is the RTC detected ?

How exactly are you connecting the RTC to the Uno ? For instance, are you using a breadboard ?

If no device is detected either way then check the integrity of the connections between the Uno and the RTC. If you have a multimeter check that the jumper wires are intact

Please post a clear photograph of the RTC board boar, both front and back

5

I am actually following and pasting someone's code and circuit diagram from Youtube and in the video it worked lol. Mine just refused not to.

6

no, i connected it directly to the board with some jumper cables or whatever you wanna call it.

okay, give me second

7

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8

The solder connections to the pins on the board do not look great
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Try reflowing them but don't overdue the heat

9

They look ok to me, although it's not a great photo.

@1von let's have a photo of the Uno also.

Do you have any other i2c devices available to test, like an OLED or LCD with an i2c backpack, or an i2c sensor of some kind?

10

I have the other one with better solder connections but they are basically the same, not working. It's just the photo quality that's making it worse

11

Unfortunately, no

12

I'm still figuring ways on how can I test it

13

Have you tried a different set of jumper wires? Sometimes the wire will break inside the insulation, making it hard to notice.

Are you powering the RTC from 5V or 3.3V? Generally you would use 5V on an UNO.

14

I've also tried with different wires, in fact, that was the first thing that I did

Yes, I'm using 5V

15

I have also tried plugging it to the SCL and SDA dedicated slot, rather than the A4 and A5

17

Apparently, I've seen a lot of issues regarding with the DS3231, I don't know if it's only common with this RTC

18

It's quite messy for now but It's actually not messy, It's just not in its proper place since I opened it

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19

The I2C scanner should be showing two devices, the DS3231 and the EEPROM chip that is on the board with the DS3231.

Have you tired with just the clock board connected to the UNO, no LCD or other wiring attached?

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20

It is messy, and that makes it difficult to check the wires, but it looks to me like they are correctly connected. The red wire is SCL and brown wire is SDA.

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I can't see where the black and white wires are connected.

1 Like
21

I rearranged everything and it finally worked. It's weird cuz I already rearranged it. Thanks for the help