DS1307 RTC library

It's a small rtc shield that i got from eBay. There are two ways to connect it using A4-A5 directly or with some sda and sdc connection.

el_pablo:
The DS1307 starts to get hot after a minute or two. Is there something wrong?

Yes. It should not be warm to the touch at all.

el_pablo:
It's a small rtc shield that i got from eBay. There are two ways to connect it using A4-A5 directly or with some sda and sdc connection.

Wow I wasn't expect this but I just bought that same one from eBay and mine almost burned me when I touched it. I really hope we didn't get ripped off :disappointed_relieved:
I am also a new and idk what to make of that... Idk el_pablo maybe if we both have the same issue we should demand a refund

I'm not sure these ebay store from China even care for their customers... I will send him the link to this thread.

This overheating problem is probably unrelated to the original post and deserves a new thread.

Right now all we know is that your 'eBay' devices are not operating properly. We have no way of knowing if you are doing something wrong or if the devices are just defective. If you provide us with a link to the eBay source we can:

(1) Possibly come up with some information to help you make your devices function properly.
or
(2) Not order from that source and avoid similar problems ourselves.

Don

This is the RTC shield that I bought.

el_pablo:
This is the RTC shield that I bought.

http://cgi.ebay.ca/DS1307-Based-Real-Time-Clock-Arduino-I2C-/230584918558?pt=LH_DefaultDomain_0&hash=item35afeea21e#ht_753wt_1139

Yup that is the same one i have. I have never worked with a RTC before and because of the complexity of the code and process of using it, it would be difficult for me to be able to tell if 1). I am not using it right 2). I broke it...? 3). or i didn't break it, it came faulty

But because i followed instruction given for a similar RTC and el_pablo has the same issues. I am getting the feeling its not our fault or we are missing some kind of instructions.

Should i email the seller? and what should i say.

PS. if our DS1307 IC got that hot does that mean that they are now fried? Because guessing by normal ebay policy i will have to pay for return shipping and for the same price i can get another new DS1307 IC...?

Well there are loads of DS1307 based RTC modules out there on the internet but I could not find any other places (besides other similar eBay sites in different countries) that sold that particular module. All of the eBay sites with that module display the same information (or lack of information).

The module is unique in that it is designed specifically for the Arduino and it should be idiot proof. Unless of course it was an idiot who designed or assembled the board. When you get an overheating chip it is frequently because the power is connected backwards. I can't tell any of this from the provided picture but it is possible that:
(1) they got the pin spacing wrong so you aren't getting 5V and GND at the left set of pins when the pins at the right are in 4 and 5.
(2) they got the wiring to 5V and GND backwards.
(3) they got the chip in backwards.

What is the labeling on the five pins opposite the Arduino? If the left one is VCC then the chip is in correctly, if it is GND then the chip is in backwards. If you provide some nice clear pictures of both sides of the board I may be able to determine if the other guesses are correct.

if our DS1307 IC got that hot does that mean that they are now fried?

Re-fried chips sometimes still function but they are frequently out of spec.

Don

HOT POTATOES ... i figured it out el_pablo you need to put 2 10k pull of resistors between the A4/A5 pins. So (A4-Arduino) and (A4-10K Resistor- 5vcc) and the same for A5...

Here is a picture

But i thought RTC module already has resistors? I can see them on the board... anyways ... a little of a pain that i have to uses external components

ds3232wiring.png

I'm pretty much a noob and I had no trouble getting my 1307 running on a breadboard without a shield. It's a pretty simple circuit.

But i thought RTC module already has resistors? I can see them on the board...

They typically are on the board but not connected unless you install a jumper. They are configured that way because if you use several I2C devices you must have only one set of pull-up resistors connected. Did your board come with any documentation.

Don

I'm pretty much a noob and I had no trouble getting my 1307 running on a breadboard without a shield. It's a pretty simple circuit.

It will run OK that way but the clock may not be accurate. There are some very specific requirements for the physical configuration of the crystal.

Don

Thanks Eric, I'll give it a try later.

EP

el_pablo:
I'm not sure these ebay store ... even care for their customers... I will send him the link to this thread.

The vendor has 100% positive approval, claims to test each item before shipping, and offers a refund if it is DOA. He probably isn't going to quibble over a $7 board.

However there is always a possibility you plugged it in the wrong way. Do you have a photo of your setup? Was it pre-wired or did you have to assemble it?

Thanks Eric, I'll give it a try later.

This may fix your failure to read the correct values from your clock chip but it has nothing to do with the overheating problem which is the part I was dealing with.

Don

Ok. I don't have the shield in my possession right now. I lend it to a friend who will check the potential issue with it.

Please let us know how you go. So far there is an implication that this vendor sells dodgy shields. It would be good to know one way or the other. And if it turns out that it is 100% definitely a bad shield, let us know how you go getting it replaced.

I know it's been way long time ago, but I just restarted to look to my "what I thought" defective clock.

I just read that the SDA and SCL are respectively on pin 20 and 21 for the Arduino Mega...

Source : Wire - Arduino Reference

How did I found out, I just bought a Duemilanove and the clock worked perfectly.

Should have RTFM!

Hi everyone,

Now, after reading through this thread, my hopes are getting back up to finally be able to use my DS1307 breakout board as well. Currently, the DS chip is getting very hot, too - within a minute.
Comparing VCC and GND, I think the chip is in the right direction. Also, the 10k resistors are soldered in already. But looking at the image posted by Eric, I am uncertain about SCL and SDA. E.g. on

, A5 is SCL and A4 is SDA - but the diagram suggests the opposite.

Eric1180:
HOT POTATOES ... i figured it out el_pablo you need to put 2 10k pull of resistors between the A4/A5 pins. So (A4-Arduino) and (A4-10K Resistor- 5vcc) and the same for A5...

Here is a picture

But i thought RTC module already has resistors? I can see them on the board... anyways ... a little of a pain that i have to uses external components

Anyhow, I attached photos of front and back of the breakout I bought on Ebay (different shop, offer is not available any more). Maybe you guys have an idea about what's wrong with it. :~

Thanks a lot,
Sven