Minds gone blank - location for USART initialisation

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Docara
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Posted by Docara: Sat. Nov 14, 2020 - 05:16 PM
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Hi it's Saturday and not had enough beer LOL

 

 

I'm going to need to change Baud rate often on across different USARTs  of a 2560.

 

1) Do I stick initialisation the normal routines (enable, start/stop, Parity, Baud) above or below int main() - (its above isn't it?)

2) Then, can I just change UBRR within the functions as needed - that's a yes right?

 

Whoever would have thought senility started at 50 aarrgghh

 

thanks

Chaps and Chapesses

 

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AVR Microcontrollers, megaAVR and tinyAVR, solved
Last Edited: Sat. Nov 14, 2020 - 05:38 PM
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Gold Markclawson
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This reply has been marked as the solution. 
Posted by clawson: Sat. Nov 14, 2020 - 05:27 PM
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Put everything to do with UART in uart.c and uart.h files - it's called "modularisation"

 

But if it is all going in the same file as main() it doesn't really matter if you put the UART  functions above or below main() but if they go below you will need DECLARATIONS above (with DEFINITIONS below).

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Docara
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Posted by Docara: Sat. Nov 14, 2020 - 05:38 PM (Reply to #2)
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Thank you for the confirmation

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Bronze Markawneil
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Posted by awneil: Sat. Nov 14, 2020 - 06:20 PM
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It's not about being "above or below main()"

 

The 'C' programming language requires that things must be declared (or defined) before they are used - that's the criterion you need to meet.

 

This is standard 'C' stuff - not specific to AVR or microcontrollers; and nothing to do with the UART.

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