John Leimgruber / Mbed 2 deprecated SerialInterrupt

A test program to recreate the system hang bug if you don't have a putc in the interrupt routine handler...

Dependencies:   mbed

main.cpp@0:e8a5f7dfa0bd, 2010-01-24 (annotated)

Committer:
leimgrub
Date:
Sun Jan 24 03:40:54 2010 +0000
Revision:
0:e8a5f7dfa0bd

        

        
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leimgrub

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#include "mbed.h"





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// Test app to cause program to suddently terminate when using serial interrupt...





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// Line 24 seems to be the important bit, but I don't really understand why?





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// Is it perhaps the putc is peroperly clearing the interrupt flag instead of the getc?





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// usb serial device defaults to 9600 baud, 8N1 on /dev/ttyACM0 (in Linux!)





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Serial pc(USBTX, USBRX); // tx, rx





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// debugging LEDs





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DigitalOut interrupt(LED1);





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DigitalOut tx(LED4);





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// one byte receive buffer





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char rx_byte;





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void handle()





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{





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  interrupt = 1;





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  //if(pc.readable()) // <--- this line doesn't matter either way...





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  {





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    rx_byte = pc.getc();





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    //pc.putc(rx_byte);  // <--- WITHOUT THIS LINE, THE APPLICATION WILL HANG IF IT RECEIVES WHILE SENDING!





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  }





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  interrupt = 0;





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  return;





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}





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int main()





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{





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  interrupt = 0;





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  tx = 0;





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  pc.attach(handle);





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  while(1) 





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  {





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    // send a long string of bytes 





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    tx = 1;





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    for(int i=0;i<20;i++)





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    {





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      pc.printf("If I receive while transmitting this I will crash...\r\n");





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    }





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    tx = 0;





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    wait(1.0);





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  }





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}