GPIO library - WiringPi

domcat

Great ..  just a question.  What do you mean with "don't have gpio-sunxi - module loaded". What do we have to care of? Something in startup?  Is there some command to avoid loading that module?

WereCatf

domcat replied at 2016-2-17 15:52
Great ..  just a question.  What do you mean with "don't have gpio-sunxi - module loaded". What do w ...

Well, it depends on your distro. I suppose most distros have it compiled as a module, so all you have to do is make sure the module is not loaded -- check with lsmod, use rmmod to unload the module if it is loaded.

Impressive

WereCatf replied at 2016-2-17 00:51
You need to know whether you need a pull-up resistor or a pull-down resistor. If whatever you've c ...

So, I tried to use pull-up and pull-down resistor in this C code, but it didn't work:

1. #include <wiringPi.h>
   
2. #include <stdio.h>
   
3. #include <drcSerial.h>
   
4. 
   
5. int main (void)
   
6. {
   
7.   wiringPiSetup();
   
8.   pinMode(6, OUTPUT);
   
9.   pinMode(7, OUTPUT);
   
10.   pinMode(8, INPUT);
    
11.   digitalWrite(7, HIGH);
    
12.   pullUpDnControl (8, PUD_DOWN) ;
    
13.   if (digitalRead(8) == HIGH)
    
14.   {
    
15.     digitalWrite(6, HIGH);
    
16.     delay(500);
    
17.     digitalWrite(6,  LOW);
    
18.     delay(500);
    
19.     digitalWrite(6, HIGH);
    
20.     delay(500);
    
21.     digitalWrite(6,  LOW);
    
22.     delay(500);
    
23.   }
    
24.   else
    
25.   {
    
26.     digitalWrite(6, HIGH);
    
27.     delay(2500);
    
28.     digitalWrite(6,  LOW);
    
29.     delay(500);
    
30.   }
    
31.   return 0;
    
32. }

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1. pinMode(6, OUTPUT);

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It's a LED

1. pinMode(7, OUTPUT);
   
2.   pinMode(8, INPUT);

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Beetwen this pins I puts the button.
So, when I switch button on/off it didn't work. LED flashed at random. I hope someone will find out how to deal with pin INPUT and button...

WereCatf

Impressive replied at 2016-2-17 17:26
So, I tried to use pull-up and pull-down resistor in this C code, but it didn't work:
It's a LED
Be ...

Yeah, it seems there is a bug in the WiringOP - library. I have merged a fix for pull-up/pull-down in my git-repo, compile WiringOP from there and it should work.

Impressive

WereCatf replied at 2016-2-17 19:05
Yeah, it seems there is a bug in the WiringOP - library. I have merged a fix for pull-up/pull-down ...

So, I compiled WiringPi from your git-repo and tried again, and ... It's works prefectly! Thank you very much!

apocalyps

So this fix should make the 433mhz sniffer beable to work because it is also interupt based

apocalyps

to be specific https://github.com/ninjablocks/433Utils this 433 util. It initially didint work because wiringOP didnt handle well on the interrupt

WereCatf

Does the code rely on digitalRead? There is an issue with digitalRead() when using interrupts on the pin and I am planning to fix it later on today -- if the pin is in mode ALT2, ie. EINT has been enabled, sunxi_digitalRead() fails and digitalRead should instead use the sysfs GPIO-interface to read the value as that seems to return the correct value. I already hacked together something, but I'm not happy with the way I did it. Alas, my boyfriend is nagging me to go and play with him, so I gotta look into it in a few hours..

WereCatf

Okay, I made a clunky workaround for digitalRead(). I don't yet know how to properly fix it, but the way I did it works for now, at least in my testing.

StaLeWaR29

how to use the hardware PWM?