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ARM FAST GPIO PROBLEM

Discussion in 'Embedded' started by abhay, Sep 22, 2006.

  1. abhay

    abhay Guest

    hi
    i m working on ARM micro LPC2138 but m unable to initialise or to make
    work its
    fast GPIO.i hav configured the settings for fast GPIO in SCS register
    but still its not working.
    i m trying this with simple example to toggle LEDs connected to port
    pins.however i can do
    the same wid legacy GPIO registers
    i want to use the additional features wid fast GPIO.
    is there any other setting for that ?
    plz do help
     
    abhay, Sep 22, 2006
    #1
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  2. So where in the LPC21"38" manual did you read that it had fast I/O?
    yes, the setting is called "LPC2148"
    RTM

    *Peter*
     
    Peter Jakacki, Sep 22, 2006
    #2
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  3. abhay

    ### AndY ### Guest

    Hi Even i have never heard about the fast GPIO in LPC2138.

    Yes but you can certainly make the processor speed faster upto 60 MHz
    using its PLL Connect Block.

    Just small settings for that to make it working on 60MHz.

    Regards,
    Anish
     
    ### AndY ###, Sep 22, 2006
    #3
  4. abhay

    abhay Guest

    hi,
    thanx for ur reply
    i m getting confused . i hav read user manual for LPC2138 where it is
    written on page 78
    that fast GPIO are available for LPC213x family.

    also i dont need fast GPIO that much for speed but i want to use its
    byte addressable &
    masking features for my applications.

    so wat i should do. plz suggest
     
    abhay, Sep 22, 2006
    #4
  5. abhay

    Mike Anton Guest

    There is nothing in the current LPC2138 manual regarding fast I/O, and
    there is certainly nothing on page 78 of the LPC2138 user manual
    that is on NXP's site. You are confused, and must be thinking of the
    LPC2148.

    I would suggest that if you must use the LPC213x series that you find
    another way to handle your masking, which could be done in software.

    Mike
     
    Mike Anton, Sep 22, 2006
    #5
  6. abhay

    CBFalconer Guest

    .. I'm . I have
    .. Also I don't I
    .. what I please

    I don't know how much of the above is due to language difficulties,
    which are forgiveable, and how much is due to laziness and failure
    to proofread, which are not. But if you are not told of the faults
    you will not be able to correct them. Correction makes your
    article much easier to read, and encourages others to respond.

    Because some of the problems are probably a language barrier, I
    have ignored faulty word order, which often seriously affects the
    English meanings.

    The apostrophe signifies a missing letter. Thus "I'm" is a
    substitute for "I am". "don't" is a substitute for "do not".
    These arise out of the normal pronunciation of the phrases. The
    first person pronoun is I (capitalized). The first word of
    sentences is always capitalized, unless referring to something like
    a lower case C identifier. Sentences are usually terminated with a
    period and two spaces. Awkward abbreviations do nothing but annoy
    the reader.

    You should also always include adequate quotations so that your
    article stands by itself. Google is not usenet, it is only a
    flawed interface to the system. See the links below.

    I hope you take this as helpful criticism. Better communications
    assist us all.

    --
    Some informative links:
    http://www.geocities.com/nnqweb/
    http://www.catb.org/~esr/faqs/smart-questions.html
    http://www.caliburn.nl/topposting.html
    http://www.netmeister.org/news/learn2quote.html
     
    CBFalconer, Sep 23, 2006
    #6
  7. abhay

    frantas Guest

    frantas, Sep 23, 2006
    #7
  8. Philips said that they would eventually upgrade the GPIO on the 2138. If
    the datasheet has just been updated then do you think that the chip that
    was produced 3 months ago or sitting on the distributors shelves will be
    upgraded as well?

    The fast GPIO parts are denoted by the /01 suffix. There are more
    enhancements such as:

    2.1 Enhancements brought by LPC213x/01 devices

    * Fast GPIO ports enable port pin toggling up to 3.5 times faster than
    the original LPC213x. They also allow for a port pin to be read at any
    time regardless of its function.

    * Dedicated result registers for ADC(s) reduce interrupt overhead.

    * UART0/1 include fractional baud rate generator, auto-bauding
    capabilities and handshake flow-control fully implemented in hardware.

    * Additional BOD control enables further reduction of power consumption.


    Once again it is the same advice, RTM....carefully.

    *Peter*
     
    Peter Jakacki, Sep 23, 2006
    #8
  9. abhay

    Mike Anton Guest

    Ok, I stand corrected. There is a new series called LPC213x/01 that does
    have fast I/O.

    Make sure you are using one of these /01 parts, or there is no fast I/O.
    Make sure you are only using the fast I/O registers. You can't mix fast
    and slow I/O. If fast I/O is enabled, you must use the fast I/O registers,
    the slow I/O registers will not work.

    Mike
     
    Mike Anton, Sep 24, 2006
    #9
  10. abhay

    frantas Guest

    Peter Jakacki escreveu:
    I didn't say that, not even implied.
    Yes, you can see it in my post.

    As you said ' yes, the setting is called "LPC2148"', I thought maybe
    you were not aware of the new parts.

    Regards,
     
    frantas, Sep 24, 2006
    #10
  11. This was taking into account the OP who may misread your reply and still
    think that his 2138 should have fast I/O. Tacking a suffix onto a part
    will not draw attention to the fact that it is a different part you are
    talking about unless you emphasize that, especially as it is so new.
    Only in retrospect.

    Truth be known I was not aware that Philips/NXP had released them yet. I
    notice that my last weekly "Philips Semiconductor News" was received
    last month. I am sure they would have announced this /01 part in the
    weekly bulletin but maybe with all the brand name changes this e-feature
    is still being updated.

    Thank-you for bring the /01 to my attention.

    *Peter*
     
    Peter Jakacki, Sep 24, 2006
    #11
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