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Problem output ports
Posted: Tue Jul 24, 2012 7:39 pm
by wayne millard
Hi
The problem that i have is that i read a input on port A0 and it seems to affect output ports. if i output a logic one on any of the ports it go's to 5V if i set the port to 0V it go's to 3.2v and only go's to 0v if i connect A0 to 0V.
Can someone help?
Wayne Millard

Re: Problem output ports
Posted: Tue Jul 24, 2012 8:13 pm
by kersing
A little more information (what hardware are you using, which version of flowcode? I suspect the PIC version, but am I right? What is the target chip, which ports are you using for output, what is connected to the output ports) might be useful. A minimal FC that demonstrates the problem would be useful as well.
Re: Problem output ports
Posted: Tue Jul 24, 2012 8:55 pm
by wayne millard
Hi kersing
Im using a 18F4520 and i have used port C and port D.
And using Flowcode V5
Thanks for any help
Wayne Millard
Re: Problem output ports
Posted: Tue Jul 24, 2012 10:12 pm
by Benj
Hello Wayne,
Which version of v5 are you using? I think v5.2 is the current latest for PIC.
Are you controlling the output of the ports based on the input from RA0 at all? Maybe caused by a floating input pin?
Have you got caps near the chip? Are you using our hardware or your own board?
Re: Problem output ports
Posted: Tue Jul 24, 2012 10:16 pm
by wayne millard
Hi Benj,
Thanks for getting back to me out of hours.
im using output masking i control one output to control direction of a motor and one output that is timed from timer2 interupt for 5 seconds then go's low.
I have a contact closer that controls the direction and rs232 can do this as well.
Im using v5.2 and the input pin has a pull up on it.
Thanks
Wayne

Re: Problem output ports
Posted: Tue Jul 24, 2012 10:20 pm
by wayne millard
Hi Benj,
im using a pcb that i have made. and all ic's have 100n as standed.
Wayne
Re: Problem output ports
Posted: Wed Jul 25, 2012 2:01 pm
by Enamul
Hi,
you said...
Im using a 18F4520 and i have used port C and port D.
At the same time you are saying...
The problem that i have is that i read a input on port A0 and it seems to affect output ports. if i output a logic one on any of the ports it go's to 5V if i set the port to 0V it go's to 3.2v and only go's to 0v if i connect A0 to 0V.
So, do you mean that input at A0 is affecting output in PORTC or PORTD which is quite surprising? Are you using any of the ADC channel?
Enamul