B4R Question watchdog in B4r

[MbedAndroid]

Most applications uses a wathdog.
In avr/arduino this is a buildin timer
I made small inline C code which init the watchdog, and resets the watchdog.
So far so good. But for test i dont give a resetwatchdog, thus the watchdog fires.
Then something happens which is not normal
The arduino comes in a kind of loop, see the LED flashing fast, and it isnt possible to load new application.

anyone knows why? The arduino should reboot, but hangs in some loop. Even pressing the resetswitch doesnt work.

#if C

#include <avr/wdt.h>
void WatchdogInit (B4R::Object* o) {
   wdt_enable (WDTO_2S);
}   
void WatchdogReset (B4R::Object* o) {
wdt_reset ();
}
void wdt_disable (B4R::Object* o) {
wdt_disable() ;
}
#End if

calling the init is like:

RunNative("WatchdogInit", Null)

calling the reset is line

RunNative("WatchdogReset", Null)

 

[Erel]

There are issues with Arduino watch dog feature that can break the boot loader which means that you will not be able to upload new sketches.

This is why it is not implemented in B4R. Search google and you will see many discussions about this issue.

 

[MbedAndroid]

the solution is given in this link https://bigdanzblog.wordpress.com/2014/10/23/installing-the-optiboot-loader-on-an-arudino-nano-to-fix-the-watch-dog-timer-wdt-issue/
will check it really works
a watchdog is really needed when devices need to run 24/7 and no surveillance is there

 

[Erel]

Another option is to reset the board every x minutes: http://www.instructables.com/id/two-ways-to-reset-arduino-in-software/?ALLSTEPS

 

[MbedAndroid]

Another option is to reset the board every x minutes: http://www.instructables.com/id/two-ways-to-reset-arduino-in-software/?ALLSTEPS

that isnt a watchdog application
A watchdog should become active when the program beconme nuts in some undefined loop

Anyway
i tried this optiboot loader, doesnt work with B4R
Then i tried a small program in visual studio, there also i cant use the watchdog. the board simply doesnt reboot
need to check the schematic why also the reset button doesnt work in a C# program

 

[Erel]

that isnt a watchdog application

It is not a watchdog but it can solve the problem.

 

[MbedAndroid]

should it be possible to intercept the watchdog ISR? What will happen when i insert inline C with the watchdog ISR vector?
Are global interrupts enabled in B4R? (sei())

 

[Erel]

You can add any C code you like. It will work.

As a general rule you should be very careful with interrupts. B4R code should never run from an interrupt. You can see an example of intercepting an interrupt event in rWire library.

 

[MbedAndroid]

this inline code works perfect -for the moment-
reset the arduino without hanging
no need for optiboot loader

#if C
ISR(WDT_vect)
{
asm volatile ("  jmp 0");
}

#include <avr/wdt.h>
void WatchdogInit (B4R::Object* o) {

wdt_enable(WDTO_8S );
cli();
WDTCSR =(1<<WDIE);
sei();  // Enable the Interrupts
}  

void WatchdogReset (B4R::Object* o) {
wdt_reset ();
}

void wdt_disable (B4R::Object* o) {
wdt_disable() ;
}
#End if

 

[peng250]

Hi,I added your code to my Arduino side program, but compiler gets error. How I can add it correctly?

#include <Stepper.h>
int c1 = 9;
int c2 = 10;
int c3 = 11;
int c4 = 12;

int Pulse;
int Speed;

Stepper motor(200, c1, c2, c3, c4);

void setup() {
  pinMode(c1, OUTPUT);
  pinMode(c2, OUTPUT);
  pinMode(c3, OUTPUT);
  pinMode(c4, OUTPUT);
while(!Serial);
 Serial.begin(9600);
}

void loop() {
  if (Serial.available())
  {
    Pulse = Serial.parseInt();
    Speed = Serial.parseInt();
    
     motor.setSpeed(Speed);
     motor.step(Pulse);
     delay(0.5);
      
  }
 
}

 

[MbedAndroid]

what error did you got?

 

[Chris Tyrie]

Is that problem with corrupting the bootloader just the Nano or does the mega have it too?