• State
  • Locked Locked
  • Replies 4 replies
  • Subscribers 80 subscribers
  • Views 580 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

12MHz Crystal?

Curt Carpenter
Expert 1255 points

Other Parts Discussed in Thread: MSP430G2211, MSP430F1612

OK, now I'm confused.  I look at the data sheet for the MSP430g2211, and I don't see any information about using a 12MHz crystal, although it appears that f(system) can be as high as 16MHz at 3+VCC.  I look at the Launchpad user's guide and get the impression that I can use a 12MHz crystal if XT2CLK is available on-chip -- but the data sheet doesn't seem to indicate that it IS available.   So I'm confused.   Can I use a 12MHz crystal on the Launchpad with my MSP430g2211?  If so -- can anyone tell me where I'll find info. on that option in the docs? 

  • 0
    Expert 2855 points

    Hi,

    The MSP430F2xx family user’s guide (Fig.5.1 footnote on page 279) let us know that devices MSP430F20xx, MSP430G2xx1, MSP430G2xx2 and MSP430G2xx3: LFXT1 does not support HF mode, XT2 is not present, and ROSC is not supported. So, you can only populate your launchpad with a 32768 Hz crystal.

     

    Don’t make confusion with the 12Mhz that drives the MSP430F1612 that implements the eZ430 FET.

     

    Best Regards,

    AES

  • 0 in reply to Antonio Espirito-Santo
    Guru 227245 points

    AES said:
    So, you can only populate your launchpad with a 32768 Hz crystal.

    Or with a HF oscillator (attached to XIN pin).

    Experiments have shown that, despite of the limitaitons given in the datasheet, you can attach an HF signal to the XIN pin in byass mode. Just not a crystal. A 4-pin oscilaltor with TTL output is fine.

  • 0 in reply to Jens-Michael Gross
    Expert 2855 points

    Hi Jens

    Jens-Michael Gross said:
    you can attach an HF signal to the XIN pin in byass mode

    Respecting fabrication recommendations increases the probability of success of a project. In this particular case, increasing the frequency of operation will have consequences on product longevity. So, I always say: follow datasheet recommendations, just in case ;).

    But you know, do as I say (not as I do).

    Best Regards,

    AES

  • 0 in reply to Antonio Espirito-Santo
    Guru 227245 points

    AES said:
    Respecting fabrication recommendations increases the probability of success of a project.

    If you look at the thread where this was first discussed, you'll see that I made almost exactly the same comment :)

    However, if you need this functionality and it cannot be obtained otherwise, it is an eat-or-die decision :)

**Attention** This is a public forum