Hello,

I cloned the master branch of WiringOP one month ago, it reported same version 2.46 and it was working except for the option to activate internal pull up/down.

Trying it in C code using:

pullUpDnControl(n, PUD_DOWN);

or by terminal with:

gpio mode 1 down

same behavior, nothing happen.. by default, unfortunately in my case, it seem active a pull up resistor for all inputs.

 

I searched on the web and found there was a bug, fixed.

I checked again the main branch and in effect it is different now, the new code is:

    *(gpio + GPPUD)              = pud & 3 ;		delayMicroseconds (5) ;
    *(gpio + gpioToPUDCLK [pin]) = 1 << (pin & 31) ;	delayMicroseconds (5) ;
    
    *(gpio + GPPUD)              = 0 ;			delayMicroseconds (5) ;
    *(gpio + gpioToPUDCLK [pin]) = 0 ;			delayMicroseconds (5) ;

but executing it I get "segmentation fault", debugging deeply the reason is that "gpio" address is zero.

 

I tried to clone the "next" branch but it is even worst, it won't compile, many errors, log from terminal attached.

 

What I can do in order to fix.. of simply to setup all inputs with pulldown resistor active?

Thanks in advance

Andrea

 

log.txt

Hello Andrea, I have the same wiringOP version and also in my case it seems the Orange Pi pulls the input UP by default without considering the SW setup cmd (pullUpDnControl(0, PUD_DOWN);) --- By the way I'm using a OPi ZERO.

Is there somebody that can help with a solution or just a workaround?

At the moment I've added a pull-down resistor of 1.8kOhm. Therefore the two voltage states are 1.0 and 2.1 (instead of 0 and 3.3). It works but I'm wondering if it is possible to improve. 

Many thanks!

Edited October 3, 20233 yr by SergioAiello

Additionally the cmd gpioRead stops working after ISR setup

 

   printf (" main1 - %d\n", digitalRead (2));

   wiringPiISR (2, INT_EDGE_BOTH, myInterrupt1) ; 
   printf (" main2 %d\n", digitalRead (2));
 

output:

root@MansaConsMon:/home/lapamo15/GPIO/wiringOP# ./ottobre2023
 main1 - 1
 main2 - 0
Waiting ...
 

And 'gpioRead' output will not change even if the INPUT toggles between 3.3 and 0V

Note: the interrupt function detects correctly the input changes, but the 'digitalRead' output is always LOW

Interrupt function triggered by the rising edge.

Signal level at input '2' is 3.3V (measured by a tester) and the command 'gpio read 2' output is '0' (which should be '1').

 

It seems there is a conflict between 'wiringPiISR' and 'digitalRead'.

 

Edited October 6, 20233 yr by SergioAiello