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Problem with IORD_ALTERA_AVALON_PIO

Altera_Forum
Honored Contributor II
1,155 Views

hi, 

i want to write a simple code witch can turn on a led when i press a button. 

i have write this piece of code but seems doesn't works... 

 

here is my code: 

 

int main() { volatile long BOUTONS_ON; while(1) { BOUTONS_ON = IORD_ALTERA_AVALON_PIO_DAT(KEY_LINE_BASE); if ((BOUTON_ON & 0x1) == 0x1) { Led2_ON(); } else { Led2_OFF(); } } return 0; }  

the build works but  

the instruction seems to be always true Led2 is always turned ON. 

maybe i have missed something or my code must be writted diffrently
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Altera_Forum
Honored Contributor II
418 Views

As a first check I's swap the ON/OFF over - and see if the led is now off! 

That should let you find out whether the problem is with the leds or switch. 

 

As written you'll need to be holding down the switch to have any effect. 

 

You might also try a software delay loop inverting the led after each delay.
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Altera_Forum
Honored Contributor II
418 Views

Change if ((BOUTON_ON & 0x1) == 0x1) to 

 

if (BOUTON_ON > 0)
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Altera_Forum
Honored Contributor II
418 Views

with your test waiyung it will be always Wrong. 

i give you my source code maybe you will see something wrong: 

http://sega4ever.power-heberg.com/fpga/test2.rar
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