PCBNEW just confirms the ERC, namely that the two VCC pins are connected 
to two different rails.

Regards,

Robert.

On 16/03/2010 18:23, daystar1013 wrote:
> Well, On your two micros, I suggest that you forget ERC and check your 
> NETLIST or better yet open the design in PCBNEW and verify that you do indeed 
> have two power rails.
>
> --- In kicad-users@yahoogroups.com, Robert<birmingham_spi...@...>  wrote:
>>
>> Thanks for your replies Carl and Andy.
>>
>> Speaking for myself, I have designs that use two instances of the same
>> micro, with each instance on a different supply rail.   These micros all
>> have a power pin named VCC and I have no problems with ERC, so Kicad
>> isn't covertly connecting my VCC pins together.
>>
>> The OP (Mark) wants to have logic chips on two different supply rails,
>> but it seems that Kicad joins up all the hidden pins marked Vcc, even if
>> you connect the power pin to a different rail.   Is the critical factor
>> that the pins are hidden, is it that the name case sensitive, or is it a
>> feature of multi-part components?   It's not that the pin doesn't have a
>> number, because the logic chip symbols have both name and number
>> specified for the power pins (like the symbols I have created for
>> myself).   What is the critical thing that Mark has to change to allow
>> him to connect two logic chips to two different supply rails.
>>
>> Regards,
>>
>> Robert.
>>
>>
>>
>> On 16/03/2010 11:14, Andy Eskelson wrote:
>>> Vcc IS the power to the chip, U2A in this case.
>>> so why have you connected +5V to it as well?
>>>
>>> DRC is detecting that you have effectively shorted VCC  to a different 5V
>>> supply as well, and is complaining about it.
>>>
>>> Power flags are defined as power out pins, and you only have one power
>>> out on a power net,m if you add a second power flag DRC will complain
>>> about that as well.
>>>
>>> I think you are assuming that you need to connect 5 volts to the chip,
>>> and so are adding the +5V port, which is another independent supply net.
>>> Hence the confusion.
>>>
>>> The system works as has been mentioned by the power port names. When a
>>> device has a power pin with a specific name, AND you set the pin to be
>>> invisible you DO NOT need to connect anything else to it. As soon as you
>>> put a power port with the same name onto the circuit diagram, that port is
>>> automatically connected to all device power pins with the same name.
>>>
>>>
>>> A power net needs to be energised or DRC will complain. That can be done
>>> in two ways. Either a device such as a regulator can have a power out
>>> pin, which will indicate that it is energised, OR you add a power flag,
>>> which simply says that the net is energised. You use power flags in
>>> situations where you are connecting an external power source to your
>>> circuit via a connector, flying leads and so on.
>>>
>>> The one oddity is that GND is considered a power out type net as well, so
>>> it also needs energising with a power flag.
>>>
>>> logic IC's have generally had their power pins identified by names
>>> rather than the voltage, so you have Vcc Vss Vdd and so on.
>>>
>>> When you run into such chips, the same will apply, power ports of the
>>> same name are already considered to be connected to the physical supply
>>>
>>> Andy
>>>
>>>
>>>
>>>
>>>
>>> On Mon, 15 Mar 2010 16:13:15 -0000
>>> "mtheling"<p...@...>   wrote:
>>>
>>>> Hi Robert,
>>>>
>>>> if I connect for example a net "+5V" to a component U2A which has an VCC 
>>>> input as invisible pin, I see that  in PCBnew the pin is connected to the 
>>>> "+5V" net as soon as I set an Powerflag to +5V.
>>>> But the ERC check in eeschema states this as error :
>>>> ErrType(5): Conflict problem between pins. Severity: error
>>>>       @ (5,1000 ",6,7500 "): Cmp #FLG01, Pin 1 (power_out) connected to
>>>>       @ (4,4000 ",6,7500 "): Cmp #FLG06, Pin 1 (power_out) (net 3)
>>>>
>>>> If I don't connect a Powerflag to the "+5V" net, in PCBnew the Power Pin 
>>>> of U2A is still connect to the VCC net and not to "+5V" as set in the 
>>>> schematic.
>>>> Please see schematic for example:
>>>> http://www.swapout.de/example_schematic.pdf
>>>>
>>>> What I am doing wrong?
>>>>
>>>> Thank you,
>>>>
>>>> best Regards,
>>>> Mark
>>>>
>>>>
>>>>
>>>>
>>>> ------------------------------------
>>>>
>>>> Please read the Kicad FAQ in the group files section before posting your 
>>>> question.
>>>> Please post your bug reports here. They will be picked up by the creator 
>>>> of Kicad.
>>>> Please visit http://www.kicadlib.org for details of how to contribute your 
>>>> symbols/modules to the kicad library.
>>>> For building Kicad from source and other development questions visit the 
>>>> kicad-devel group at http://groups.yahoo.com/group/kicad-develYahoo! 
>>>> Groups Links
>>>>
>>>>
>>>>
>>>
>>>
>>> ------------------------------------
>>>
>>> Please read the Kicad FAQ in the group files section before posting your 
>>> question.
>>> Please post your bug reports here. They will be picked up by the creator of 
>>> Kicad.
>>> Please visit http://www.kicadlib.org for details of how to contribute your 
>>> symbols/modules to the kicad library.
>>> For building Kicad from source and other development questions visit the 
>>> kicad-devel group at http://groups.yahoo.com/group/kicad-develYahoo! Groups 
>>> Links
>>>
>>>
>>>
>>>
>>>
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>
>
>
>
> ------------------------------------
>
> Please read the Kicad FAQ in the group files section before posting your 
> question.
> Please post your bug reports here. They will be picked up by the creator of 
> Kicad.
> Please visit http://www.kicadlib.org for details of how to contribute your 
> symbols/modules to the kicad library.
> For building Kicad from source and other development questions visit the 
> kicad-devel group at http://groups.yahoo.com/group/kicad-develYahoo! Groups 
> Links
>
>
>
>
>
>
> No virus found in this incoming message.
> Checked by AVG - www.avg.com
> Version: 9.0.790 / Virus Database: 271.1.1/2750 - Release Date: 03/16/10 
> 07:33:00
>
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Checked by AVG - www.avg.com 
Version: 9.0.790 / Virus Database: 271.1.1/2750 - Release Date: 03/16/10 
07:33:00

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