RTC only counts when I touch the device

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Rena

Rena

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I've added a crystal to a Teensy 3.2, but the RTC only advances if I touch some parts of the Teensy with my finger. I've resoldered it, and it doesn't happen if I touch with plastic, so what's going on here? Some capacitance issue?
 
Looks like the 32kHz crystal does not oscillate without additional capacitance. Which is the brand and type of your crystal?
 
The package doesn't say much useful:

XTAL 32.768KHZ CYLINDRICAL 3X8MM
DWA-1227B-1
MCRY-1001-TF3X8
1 PCS/PKG
193640
Click to expand...

I could add a capacitor, but I'm not sure where or what capacitance. I tried messing with the RTC_CR_SCxP bits but they didn't help.
 
Probably better and easier to order and replace with the specified crystal. It might function with some range of capacitors properly added - but may not be accurate - and perhaps subject to noise from the added component?

from :: pjrc.com/teensy/td_libs_Time.html
To use the Teensy 3.0, 3.1 & 3.2 RTC, you must add a 32.768 kHz, 12.5 pF crystal to the bottom side of the board. The crystal shown is Citizen part CFS-206, Digikey part 300-8303-ND, 300-8762-ND, 300-8763-ND, or 300-1002-ND. Teensy 3.5 & 3.6 have this 32.768 kHz crystal built in.
Click to expand...

I bought a 10 pack of inexpensive crystals matching this spec - probably from Amazon and they worked on the T_3.1/2 I put them on - though I never did any specific RTC testing of the timekeeping.
 
Order soon and pay for fast delivery :) I can't help with EE part of saying what could go where to make it work.
 
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