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Visitor II
December 28, 2005
Question

UART & USB Run Together

  • December 28, 2005
  • 3 replies
  • 778 views
Posted on December 28, 2005 at 03:06

UART & USB Run Together

    This topic has been closed for replies.

    3 replies

    sgAuthor
    Visitor II
    May 17, 2011
    Posted on May 17, 2011 at 12:09

    Hi,

    I am new Firmware programmer. I gone through the UPSD3234A's Datasheet, it said the USB must run on 12, 24, 36MHz for MCU. I was wonder how am i able to have UART0, and USB together on a single design and run. because with 12, 24, 36MHz, i cannot get my desired baudrate, eg, 9600, 19200.

    Please Advise.

    Visitor II
    May 17, 2011
    Posted on May 17, 2011 at 12:09

    Using Timer2 as baudrate generator, 9600Baud is possible with 12MHz crystal with negligible (0.16%) error; similarly 19200Baud with 24MHz crystal.

    A good tool for baudrate calculation is at the Keil pages:

    http://www.keil.com/c51/baudrate.asp

    Jan Waclawek

    sgAuthor
    Visitor II
    May 17, 2011
    Posted on May 17, 2011 at 12:09

    THANKS A LOT. I TRIED ON IT, IT DOES HAVE SOME SMALL PERCENTAGE OF FAULTY ON 9600 BAUDRATE. ANYWAY, I GUESS I STILL STICK ON UART DESIGN.

    tHANKS.