hi,
plugging my Pi to my 12V/5V DC /DC converter, the Pi don't boot, the screen shows
"sh: can't access tty: job control turned off /#"
( 2 different converters, same error)
re-plugging to a 230V/5V AC/DC wall converter, the Pi boots fine.
Unfortunately I can't measure the voltage of the USB plug.
what is going wrong?
sh: can't access tty: job control turned off /#
#define S sqrt(t+2*i*i)<2
#define F(a,b) for(a=0;a<b;++a)
float x,y,r,i,s,j,t,n;int main(){F(y,64){F(x,99){r=i=t=0;s=x/33-2;j=y/32-1;F(n,50&S){t=r*r-i*i;i=2*r*i+j;r=t+s;}if(S){PointOut(x,y);}}}for(;;);}
#define F(a,b) for(a=0;a<b;++a)
float x,y,r,i,s,j,t,n;int main(){F(y,64){F(x,99){r=i=t=0;s=x/33-2;j=y/32-1;F(n,50&S){t=r*r-i*i;i=2*r*i+j;r=t+s;}if(S){PointOut(x,y);}}}for(;;);}
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davidcoton
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Re: sh: can't access tty: job control turned off /#
The Klingons are coming?davenull wrote: what is going wrong?
It is absolutely impossible to tell, without knowing:
1) the current consumption of your Pi and peripherals, which will depend partly on the model of Pi
2) The actual output voltage under load of each supply
3) The rated (or better, actual) current limit of each supply.
Since the Pi works on one supply, a good working hypothesis is that the DC/DC converters are not providing enough voltage under load.
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Re: sh: can't access tty: job control turned off /#
I have a Pi 2,
on the DC converter label is written "5V 3A" (4A short) ,
the wall plug is 5V 2A.
But this error message above is known to be shown at low voltage?
on the DC converter label is written "5V 3A" (4A short) ,
the wall plug is 5V 2A.
But this error message above is known to be shown at low voltage?
Last edited by davenull on Thu May 05, 2016 10:38 pm, edited 1 time in total.
#define S sqrt(t+2*i*i)<2
#define F(a,b) for(a=0;a<b;++a)
float x,y,r,i,s,j,t,n;int main(){F(y,64){F(x,99){r=i=t=0;s=x/33-2;j=y/32-1;F(n,50&S){t=r*r-i*i;i=2*r*i+j;r=t+s;}if(S){PointOut(x,y);}}}for(;;);}
#define F(a,b) for(a=0;a<b;++a)
float x,y,r,i,s,j,t,n;int main(){F(y,64){F(x,99){r=i=t=0;s=x/33-2;j=y/32-1;F(n,50&S){t=r*r-i*i;i=2*r*i+j;r=t+s;}if(S){PointOut(x,y);}}}for(;;);}
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davidcoton
- Posts: 5027
- Joined: Mon Sep 01, 2014 2:37 pm
- Location: Cambridge, UK
- Contact: Website
Re: sh: can't access tty: job control turned off /#
Not to me, but that may not be significant.davenull wrote:I have a Pi 2,
on the DC converter label is written "5V 3A",
the wall plug is 5V 2A.
But this error message above is known to be shown at low voltage?
What is the current capacity of your 12V source?
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Re: sh: can't access tty: job control turned off /#
15Ah, currently 12.8V
#define S sqrt(t+2*i*i)<2
#define F(a,b) for(a=0;a<b;++a)
float x,y,r,i,s,j,t,n;int main(){F(y,64){F(x,99){r=i=t=0;s=x/33-2;j=y/32-1;F(n,50&S){t=r*r-i*i;i=2*r*i+j;r=t+s;}if(S){PointOut(x,y);}}}for(;;);}
#define F(a,b) for(a=0;a<b;++a)
float x,y,r,i,s,j,t,n;int main(){F(y,64){F(x,99){r=i=t=0;s=x/33-2;j=y/32-1;F(n,50&S){t=r*r-i*i;i=2*r*i+j;r=t+s;}if(S){PointOut(x,y);}}}for(;;);}
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davidcoton
- Posts: 5027
- Joined: Mon Sep 01, 2014 2:37 pm
- Location: Cambridge, UK
- Contact: Website
Re: sh: can't access tty: job control turned off /#
I assume by that it is a battery of some sort, so not likely to be incapable of the load (I should have said "current LIMIT of your 12V source").
What OS or boot system is producing the error message?
What OS or boot system is producing the error message?
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Re: sh: can't access tty: job control turned off /#
current, I see: about 20A
it's actually 6x packs parallel of 10 x 1.2V 2600mAh NiMH RC batteries,
I am booting Jessie from a NOOBS SD card
it's actually 6x packs parallel of 10 x 1.2V 2600mAh NiMH RC batteries,
I am booting Jessie from a NOOBS SD card
#define S sqrt(t+2*i*i)<2
#define F(a,b) for(a=0;a<b;++a)
float x,y,r,i,s,j,t,n;int main(){F(y,64){F(x,99){r=i=t=0;s=x/33-2;j=y/32-1;F(n,50&S){t=r*r-i*i;i=2*r*i+j;r=t+s;}if(S){PointOut(x,y);}}}for(;;);}
#define F(a,b) for(a=0;a<b;++a)
float x,y,r,i,s,j,t,n;int main(){F(y,64){F(x,99){r=i=t=0;s=x/33-2;j=y/32-1;F(n,50&S){t=r*r-i*i;i=2*r*i+j;r=t+s;}if(S){PointOut(x,y);}}}for(;;);}
Re: sh: can't access tty: job control turned off /#
no idea what was going on.
I unplugged the T-Cobbler and all power source cables from the devices, and replugged them all anew.
Now it's fine again, just like it was before with the battery source.
I unplugged the T-Cobbler and all power source cables from the devices, and replugged them all anew.
Now it's fine again, just like it was before with the battery source.
#define S sqrt(t+2*i*i)<2
#define F(a,b) for(a=0;a<b;++a)
float x,y,r,i,s,j,t,n;int main(){F(y,64){F(x,99){r=i=t=0;s=x/33-2;j=y/32-1;F(n,50&S){t=r*r-i*i;i=2*r*i+j;r=t+s;}if(S){PointOut(x,y);}}}for(;;);}
#define F(a,b) for(a=0;a<b;++a)
float x,y,r,i,s,j,t,n;int main(){F(y,64){F(x,99){r=i=t=0;s=x/33-2;j=y/32-1;F(n,50&S){t=r*r-i*i;i=2*r*i+j;r=t+s;}if(S){PointOut(x,y);}}}for(;;);}
Re: sh: can't access tty: job control turned off /#
My guess is that the T-Cobbler (or whatever was on the other end of it) wasn't connected properly and it was pulling pin 5 (GPIO3) low, which triggers a special "recovery mode".davenull wrote:no idea what was going on.
I unplugged the T-Cobbler and all power source cables from the devices, and replugged them all anew.
Now it's fine again, just like it was before with the battery source.
Re: sh: can't access tty: job control turned off /#
yes, perhaps, although I don't and didn't plug anything to the GPIO.3 pin...
anyway, it's fine FTM.
Thank you!
anyway, it's fine FTM.
Thank you!
#define S sqrt(t+2*i*i)<2
#define F(a,b) for(a=0;a<b;++a)
float x,y,r,i,s,j,t,n;int main(){F(y,64){F(x,99){r=i=t=0;s=x/33-2;j=y/32-1;F(n,50&S){t=r*r-i*i;i=2*r*i+j;r=t+s;}if(S){PointOut(x,y);}}}for(;;);}
#define F(a,b) for(a=0;a<b;++a)
float x,y,r,i,s,j,t,n;int main(){F(y,64){F(x,99){r=i=t=0;s=x/33-2;j=y/32-1;F(n,50&S){t=r*r-i*i;i=2*r*i+j;r=t+s;}if(S){PointOut(x,y);}}}for(;;);}