Narendran Pandian

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11 years, 5 months ago.

How do you connect an external oscillator to kl25z?

I have been trying to figure this out on my own but I do not know what pins to connect to ( PTC i guess). Anybody can help me with a program snippet and pin details

Hello Narendran Pandian,

can you be more specific, what type of external oscillator you wnat to connect? do you have your own board? Or using FRDM-KL25Z? There is polluted 8MHz crystal, and the 32kHz for RTC (RTC_IN pin) is generated from the interface chip on board (called openSDA).

posted by Martin Kojtal 24 Mar 2014

2 Answers

Paul Staron
11 years, 5 months ago.

If you are looking for the RTC to work properly on a KL25Z there is an alternative approach using a 32kHz crystal in place of the 8Mhz crystal, see here:

http://mbed.org/users/star297/code/KL25Z-32kHz-crystal-mbed-src/

Accepted Answer
Narendran Pandian
poster
11 years, 5 months ago.

I am going to use a crystal oscillator 4MHZ . I usually connect it to the OSC1 and OSC2 pins in PIC16f877A. Can you tell me the similar or equivalent pins to be used in the FRDM KL25Z

You can look at the schematic, but the equivalent oscillator pins of the KL25Z are already used for an 8MHz crystal. Why do you want an additional 4MHz oscillator?

posted by Erik - 24 Mar 2014