PMOD RTCC Battery and connections

[ksamuelson]

You  may file this in the stupid question category but I didn't see anywhere that said what battery you suggest for the PMOD RTCC?  Obviously there is a certain size that "fits" in the carrier but I didn't want to just try a bunch of batteries only to find out it was the wrong one. Can you provide a "suggested" battery number and voltage? 

This information would be helpful to put on the Reference material or datasheet 

Also I see on the Reference page, https://reference.digilentinc.com/reference/pmod/pmodrtcc/reference-manual,  it says Pin 1 & 5 is SCL and 2& 6  is SDA  but on the schematic it show 1&2 connected (shorted) as SCL and 3 & 4 shorted as SDA.  I'm plugging this into a bread board so it is important that the pins do not get shorted.  Can you provide the correct information?  I guess no one actually reads documentation anymore or no one uses this part. 

I will be connecting this to ARTY but from what I can tell you don't have a reference design.  This would be a nice addition. 

[ksamuelson]

Sorry it looks like I found it in the "old" manual - https://reference.digilentinc.com/pmod/pmod/rtcc/old_ref_manual 

 

The PmodRTCC has a holder for a 12mm lithium coin cell to power the RTCC and SRAM if VDD should ever fall below the operating point. In order to enable this power back-up, the VBATEN bit must be set in the RTCC registers. Compatible coin cells include BR1216, CR1216, BR1220, CL1220, CR1220, and BR1225.

 

Is this information correct. 

About the pinouts this page matches the schematic not the new page.

[jpeyron]

Hi Ksamuelson,

Sorry about the confusion with the schematic. The pins are tied vertically. Per the reference manual SCL is pin1 on the top and pin 5 directly below, SDA will be pin 2 on the top next to pin 1 and directly below pin 6 next to pin 5. Gnd will be next top and bottom pins and after that VCC will be the last pins.I have included a picture below.

thank you,

Jon

20160930_150720.zip

[ksamuelson]

Thank you for the clarification.  I saw what was on the board but have learned not to trust the markings.  So I went to the schematic and was confused.  All clear now. 

 

[Loredana]

Hello @ksamuelson,

Did you manage to integrate the RTC in your design?

Is there any IP for this? Or some tutorials, example code? 

Thanks!