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		| MCUprogrammer 
 
 
 Joined: 08 Sep 2020
 Posts: 233
 
 
 
			    
 
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				| rs232 communication |  
				|  Posted: Thu Dec 28, 2023 9:17 am |   |  
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				| How can I create a control code to detect if the connection is lost during communication via RS232? Would you help me with this topic? _________________
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 MCUprogrammer
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		| Ttelmah 
 
 
 Joined: 11 Mar 2010
 Posts: 19967
 
 
 
			    
 
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				|  Posted: Thu Dec 28, 2023 9:27 am |   |  
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				| Of itself, serial does not have any detection of the 'state' of the connection. A lot depends on the nature of what is being sent, and how the wiring is done?.
 So (for example), you can wire a connection so that if the connection is not
 present the receiver is biased to the 'break' state. This will then give
 continuous received zero characters with the framing error bit set.
 Alternatively, your friend is the timeout. If you know a packet should arrive
 every second, then have a timer interrupt set to timeout at (say) 1.2 seconds,
 and reset this whenever a packet arrives. If this triggers the connection has
 been lost.
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		| MCUprogrammer 
 
 
 Joined: 08 Sep 2020
 Posts: 233
 
 
 
			    
 
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				|  Posted: Thu Dec 28, 2023 9:57 am |   |  
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				| There are 3 connections on the device. RX,TX,GND. For example, can I do something like the following? or what can i do. 
  	  | Code: |  	  | if (kbhit(UART1)) {
 printf("There is a connection\r\n");
 } else {
 printf("No connection\r\n");
 }
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 _________________
 Best Regards...
 MCUprogrammer
 _______________________________
 Work Hard
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		| gaugeguy 
 
 
 Joined: 05 Apr 2011
 Posts: 350
 
 
 
			    
 
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				|  Posted: Thu Dec 28, 2023 10:55 am |   |  
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				| What you posted would probably not work well on its own.  You are really missing the point of the advice Ttelmah was giving. The answer relies on information you did not provide.  How does your device define a working connection?  Are the messages formatted or random?   Are messages sent at a regular interval or can the arrive at any random time?
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		| MCUprogrammer 
 
 
 Joined: 08 Sep 2020
 Posts: 233
 
 
 
			    
 
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				|  Posted: Thu Dec 28, 2023 11:04 am |   |  
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				| I solved the problem with timeout. thanks _________________
 Best Regards...
 MCUprogrammer
 _______________________________
 Work Hard
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