Tiny RTC DS1307 + 24C32 Real Time Clock Module (HCMODU0011)

Real Time Clock modules for microcontrollers
marco78
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Joined: Sat Feb 01, 2014 11:47 am

Re: Tiny RTC DS1307 + 24C32 Real Time Clock Module (HCMODU00

Post by marco78 » Sat Feb 08, 2014 4:29 pm

I have tried connecting both the pins SDA1 and SDA2 and the pins 20 and 21. In both cases I have used adafruit 4 bit converter BSS138, with LV at 3,3V and HV at 5V. I have also tried using a 1.8KOhm pull-up resistors on SDA and SCL lines, but without success.

andrew
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Re: Tiny RTC DS1307 + 24C32 Real Time Clock Module (HCMODU00

Post by andrew » Sun Feb 09, 2014 4:05 pm

It seems that when compiling for the due it doesn't like the Wire library to be initialised before the setup() function. In the HCRTC.cpp file can you comment out the Wire.begin(); function (don't forget to save it) like this:

HCRTC::HCRTC(void)
{

//Wire.begin();

}

Then in your sketch add Wire.begin(); as the first line in the setup() function.

I don't have an appropriate level shifter to hand at the moment so I can't confirm that it will fix it but it should stop getting stuck.
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marco78
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Joined: Sat Feb 01, 2014 11:47 am

Re: Tiny RTC DS1307 + 24C32 Real Time Clock Module (HCMODU00

Post by marco78 » Mon Feb 10, 2014 7:02 pm

Now it seems to work properly... :)
Thank you very much andrew

andrew
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Re: Tiny RTC DS1307 + 24C32 Real Time Clock Module (HCMODU00

Post by andrew » Tue Feb 11, 2014 9:59 am

Great. I'll make this modification the next time I update the library.
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john_m0ers
Posts: 12
Joined: Fri Feb 28, 2014 10:21 pm

Re: Tiny RTC DS1307 + 24C32 Real Time Clock Module (HCMODU00

Post by john_m0ers » Tue Apr 01, 2014 10:35 pm

Hi, After reading through all the posts, I cant find any mention of someone mounting a ds18b20 module in the three holes outlined.
What if any are the 'gotchas'
regards john

david.prentice
Posts: 3
Joined: Sun Jan 19, 2014 12:06 am

Re: Tiny RTC DS1307 + 24C32 Real Time Clock Module (HCMODU00

Post by david.prentice » Tue Apr 01, 2014 10:56 pm

The only gotcha is:

Do you really want to measure the temperature of the module pcb ?

Or the temperature at the end of an external probe?

andrew
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Re: Tiny RTC DS1307 + 24C32 Real Time Clock Module (HCMODU00

Post by andrew » Wed Apr 02, 2014 2:32 pm

@john_m0ers

We haven't tested this ourselves but I see no issues. You can access the output at the DS pin. I believe that the module places a 3.3K pullup on the data pin of the sensor.
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john_m0ers
Posts: 12
Joined: Fri Feb 28, 2014 10:21 pm

Re: Tiny RTC DS1307 + 24C32 Real Time Clock Module (HCMODU00

Post by john_m0ers » Wed Apr 02, 2014 9:15 pm

Hi,
I was thinking of the insulated ds18b20s that I got from Hobby, but I suppose in a small self contained unit
with a controller and lcd this could be useful.
The main reason for asking was that I read somewhere that a similar module burned out the ds18b20. I suppose
there could be a few reasons why that might happen though.
Anyway thanks for letting me know there are no real issues with this.
Regards john

AlanWooler
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Joined: Thu Dec 04, 2014 9:30 pm

Re: Tiny RTC DS1307 + 24C32 Real Time Clock Module (HCMODU00

Post by AlanWooler » Mon Jan 05, 2015 7:12 am

Quick question for you Andrew about this module, which is about the recharge bit of it.
These units can use the LIR2032 rechargeable batteries, so using the 4 pin headers on the left (SCL, SDA, VCC, GND) do you know if this enough for the module to charge the battery once the Arduino board is powered up, or do any of the 7 headers on the other side of the module.

andrew
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Re: Tiny RTC DS1307 + 24C32 Real Time Clock Module (HCMODU00

Post by andrew » Mon Jan 05, 2015 12:16 pm

It will charge the battery via any of the pins marked VCC and GND. You'll need to apply +5V across these pins for it to charge correctly.
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