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dsPIC33CH Curiosity Dev Board - MCC UART Baud Rate issue

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edga
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2019/07/11 00:21:30 (permalink)
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dsPIC33CH Curiosity Dev Board - MCC UART Baud Rate issue

I am dealing for the first time with a dsPIC22CH Curiosity Development Board, equipped with a dsPIC33CH512MP508 (although it is dual-core, I use it only in Master mode as if it was a single core).
 
For the sake of simplicity, I configured the UART1 module with MCC and used the functions defined in the tool-generated files 'uart1.c' and ' uart1.h'. To test their functioning, I decided to send  some dummy strings to CoolTem serial reader (with which I'm pretty acquainted).
 
With the following UART settings everything runs smoothly and I see correctly the dummy strings printed on the terminal:
  • Clock Source: Fosc/2 = 4 MHz (derived from Primary Oscillator)
  • Baud Rate: 38400
  • Parity: none
  • Data Bits: 8
  • Stop Bits: 1
But, once I set a clock source higher than 4 MHz, I do not receive the dummy strings correctly anymore, even if the baud rate is kept the same, and I see the typical non-sense random chars as if there is misalignment of Baud Rate settings between TX and RX. 
 
Checks already performed:
  • The code automatically generated by MCC is such that the equation for the final baud rate is satisfied (pag.12 of UART dsPIC33/PIC24 Family Reference manual).
  • The High Baud Rate Select bit BRGH is set to 1 and the desired Baud Rate lies within the allowed range. 
  • I've tried to derive the UART clock from other sources without obtaining differences. 
Am I missing some requirements and/or limitations? 
 
Thanks in advance
 
PS: I tried to insert URL link to redirect to the source which I mention in this post but if I keep them Forum firewall doesn't allow me to post this thread (pretty annoying, but as far as I can see it is something typical of this forum). 
#1

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    ric
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    Re: dsPIC33CH Curiosity Dev Board - MCC UART Baud Rate issue 2019/07/18 20:41:15 (permalink)

    I also post at: PicForum
    Links to useful PIC information: http://picforum.ric323.co...opic.php?f=59&t=15
    NEW USERS: Posting images, links and code - workaround for restrictions.
    To get a useful answer, always state which PIC you are using!
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    edga
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    Re: dsPIC33CH Curiosity Dev Board - MCC UART Baud Rate issue 2019/07/19 00:08:10 (permalink)
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    Sorry, my bad, still a newbie about this forum. 
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