Complete but incomplete?

On 07/09/16 17:59, Tom Storey wrote:

Working on a PCB design, and Ive completed  the layout, but Eagle is telling me there are seemingly some things that still need to be done.

 

Take the attached screen shot for example. Ive selected a net, which highlights all of the nearby pads/traces etc that are part of it. But there are airwires telling me I still need to connect something?

 

Can anyone tell me why this would be happening, and perhaps how I can get rid of them (short of connecting them the way it thinks I should, which would spoil my design.)

 

Thanks!

I assume you mean that your intent was to have multiple copies of the

same circuit, and your problem is that Eagle wants to connect them all

together? If so, the cause is almost certainly that you copied blocks of

schematic which had named nets. The names are retained in the copy,

which tells Eagle they are the same net (that's how you connect nets

between sheets, for example). You need to go back to the schematic and

rename the problematic net segments to be different.

Note that any net connected to a supply symbol is inherently named by

that connection. If you want your multiple circuits to have independent

power connections then you have to do more work.

Indeed I did duplicate blocks of circuit in my schematic. In this case the parts in question all share the same net name on purpose (+5V in this case, and one between two pads/traces part of the GND net). But although I have connected them all together, and in the screenshot I have highlighted the net named +5V and it has highlighted everything correctly, its still telling me that I need to connect them together. It doesnt seem happy with the way Ive done it, even though it would appear to be valid.

It all checks out in the gerbers that I exported, so maybe its nothing to worry about. Just thought it would be nice to see a full board without any airwires left.

Indeed I did duplicate blocks of circuit in my schematic. In this case the parts in question all share the same net name on purpose (+5V in this case, and one between two pads/traces part of the GND net). But although I have connected them all together, and in the screenshot I have highlighted the net named +5V and it has highlighted everything correctly, its still telling me that I need to connect them together. It doesnt seem happy with the way Ive done it, even though it would appear to be valid.

It all checks out in the gerbers that I exported, so maybe its nothing to worry about. Just thought it would be nice to see a full board without any airwires left.

On 07/09/16 19:01, Tom Storey wrote:

Indeed I did duplicate blocks of circuit in my schematic. In this case the parts in question all share the same net name on purpose (+5V in this case, and one between two pads/traces part of the GND net). But although I have connected them all together, and in the screenshot I have highlighted the net named +5V and it has highlighted everything correctly, its still telling me that I need to connect them together. It doesnt seem happy with the way Ive done it, even though it would appear to be valid.

 

Have you run RATSNEST on it? It's possible for unnecessary airwires to

be left if you add copper other than by the "route" tool (or even if you

route specific ways) but ratsnest forces a re-calculation.

Alternatively (and this can be hidden by a ratsnest) there may be traces

that overlap without actually joining. Eagle will consider that an

incomplete track and will leave an airwire. After re-calc that tends to

be a very short one that you'd easily miss...

Yup, have clicked ratsnest a million times while working in other areas of the board.

Theres nothing overlapping that would break or interfere with the continuity of a trace.

Tom Storey wrote:

 

Yup, have clicked ratsnest a million times while working in other areas of the board.

 

Theres nothing overlapping that would break or interfere with the continuity of a trace.

Ahhh the old immortal air wire bug. I had a board once where a single air wire stayed despite all attempts to find some minor misconnection. There wasn't one. In the end I closed the schematic, renamed the board, created a new empty board with the old name, copied everything across from the old board the the new board, closed everything down and reopened the schematic and board together and hey presto the air wire was finally gone! I never did work out what triggered it to happen but I did get it fixed this way.

Best Regards,

Rachael

On 07/09/16 21:07, rachaelp wrote:

Tom Storey wrote:

 

Yup, have clicked ratsnest a million times while working in other areas of the board.

 

Theres nothing overlapping that would break or interfere with the continuity of a trace.

Ahhh the old immortal air wire bug. I had a board once where a single air wire stayed despite all attempts to find some minor misconnection. There wasn't one. In the end I closed the schematic, renamed the board, created a new empty board with the old name, copied everything across from the old board the the new board, closed everything down and reopened the schematic and board together and hey presto the air wire was finally gone! I never did work out what triggered it to happen but I did get it fixed this way.

 

Ah... yes... there's a bug in V5 (don't know if the more recent ones fix

it) that can leave invisible bits of unwanted trace on the board. They

are associated with a net, so ratsnest adds an airwire to them, because

they are unconnected to the rest of the net.

That one didn't occur to me because the problem reported was not "a

random airwire appears that ends in middle of nowhere", which is how the

bug always seems to manifest for me.

Anyway, the solution is simple - just rip up the offending stray bit of

trace. At least, it would be simple if the said bit of trace weren't

completely invisible! So far I've always managed to fix it by MOVEing

one end of the invisible trace (at the stray end of the airwire) at

which point the trace becomes visible and can be ripped up. It usually

takes a few goes, though, because the trace isn't immediately visible to

the MOVE command, either.

CadSoft Guest wrote:

 

On 07/09/16 21:07, rachaelp wrote:

Tom Storey wrote:

 

Yup, have clicked ratsnest a million times while working in other areas of the board.

 

Theres nothing overlapping that would break or interfere with the continuity of a trace.

Ahhh the old immortal air wire bug. I had a board once where a single air wire stayed despite all attempts to find some minor misconnection. There wasn't one. In the end I closed the schematic, renamed the board, created a new empty board with the old name, copied everything across from the old board the the new board, closed everything down and reopened the schematic and board together and hey presto the air wire was finally gone! I never did work out what triggered it to happen but I did get it fixed this way.

 

Ah... yes... there's a bug in V5 (don't know if the more recent ones fix

it) that can leave invisible bits of unwanted trace on the board. They

are associated with a net, so ratsnest adds an airwire to them, because

they are unconnected to the rest of the net.

 

That one didn't occur to me because the problem reported was not "a

random airwire appears that ends in middle of nowhere", which is how the

bug always seems to manifest for me.

 

Anyway, the solution is simple - just rip up the offending stray bit of

trace. At least, it would be simple if the said bit of trace weren't

completely invisible! So far I've always managed to fix it by MOVEing

one end of the invisible trace (at the stray end of the airwire) at

which point the trace becomes visible and can be ripped up. It usually

takes a few goes, though, because the trace isn't immediately visible to

the MOVE command, either.

 

 

 

I think this was subtly different. I could get the pesky air wire to show in completely different parts of the net depending on how I ripped it all out and re-drew it. It was really really weird. In the end the only way I could find to sort it was to copy and paste everything to a new blank board and the rogue air wires were removed. Unfortunately I don't have a copy of the board in the state showing the issue anymore so I can't send it on to CADSoft to investigate.

Am 07.09.2016 um 23:12 schrieb rachaelp:

CadSoft Guest wrote:

 

On 07/09/16 21:07, rachaelp wrote:

Tom Storey wrote:

 

Yup, have clicked ratsnest a million times while working in other areas of the board.

 

Theres nothing overlapping that would break or interfere with the continuity of a trace.

Ahhh the old immortal air wire bug. I had a board once where a single air wire stayed despite all attempts to find some minor misconnection. There wasn't one. In the end I closed the schematic, renamed the board, created a new empty board with the old name, copied everything across from the old board the the new board, closed everything down and reopened the schematic and board together and hey presto the air wire was finally gone! I never did work out what triggered it to happen but I did get it fixed this way.

 

Ah... yes... there's a bug in V5 (don't know if the more recent ones fix

it) that can leave invisible bits of unwanted trace on the board. They

are associated with a net, so ratsnest adds an airwire to them, because

they are unconnected to the rest of the net.

 

That one didn't occur to me because the problem reported was not "a

random airwire appears that ends in middle of nowhere", which is how the

bug always seems to manifest for me.

 

Anyway, the solution is simple - just rip up the offending stray bit of

trace. At least, it would be simple if the said bit of trace weren't

completely invisible! So far I've always managed to fix it by MOVEing

one end of the invisible trace (at the stray end of the airwire) at

which point the trace becomes visible and can be ripped up. It usually

takes a few goes, though, because the trace isn't immediately visible to

the MOVE command, either.

 

 

 

I think this was subtly different. I could get the pesky air wire to show in

completely different parts of the net depending on how I ripped it all out and

re-drew it. It was really really weird. In the end the only way I could find

to sort it was to copy and paste everything to a new blank board and the rogue

air wires were removed. Unfortunately I don't have a copy of the board in the

state showing the issue anymore so I can't send it on to CADSoft to investigate.

 

 

As Rachael wrote, feel free to send the board to support@cadsoft.de.

So we can invsetigate.....

--

Mit freundlichen Gruessen / Best regards

Richard Hammerl

  CadSoft Support -- hotline@cadsoft.de

  FAQ: http://www.cadsoft.de/training/faq/

On 08/09/16 07:31, Richard Hammerl wrote:

 

As Rachael wrote, feel free to send the board to support@cadsoft.de.

So we can invsetigate.....

I will try to remember to do so next time it happens, especially if I

manage to get it on V7

On 08/09/16 07:49, Rob Pearce wrote:

On 08/09/16 07:31, Richard Hammerl wrote:

 

As Rachael wrote, feel free to send the board to support@cadsoft.de.

So we can invsetigate.....

 

I will try to remember to do so next time it happens, especially if I

manage to get it on V7

 

Sorry, meant to add, hopefully Tom still has his rogue to send now...

Tom Storey wrote:

Indeed I did duplicate blocks of circuit in my schematic. In this case

the parts in question all share the same net name on purpose (+5V in

this case, and one between two pads/traces part of the GND net). But

although I have connected them all together, and in the screenshot I

have highlighted the net named +5V and it has highlighted everything

correctly, its still telling me that I need to connect them together.

It doesnt seem happy with the way Ive done it, even though it would

appear to be valid.

Eagle doesn't know you intend your copies to be treated independently.

As Rob already explained: manually named nets (especially those

connected to power symbols) in the schematic don't get renamed when

copied.

So your 'independent' sub-layouts share them and eagle therefore shows

air-wires connecting them.

--

Lorenz

CadSoft Guest wrote:

 

Tom Storey wrote:

 

Indeed I did duplicate blocks of circuit in my schematic. In this case

the parts in question all share the same net name on purpose (+5V in

this case, and one between two pads/traces part of the GND net). But

although I have connected them all together, and in the screenshot I

have highlighted the net named +5V and it has highlighted everything

correctly, its still telling me that I need to connect them together.

It doesnt seem happy with the way Ive done it, even though it would

appear to be valid.

 

Eagle doesn't know you intend your copies to be treated independently.

 

As Rob already explained: manually named nets (especially those

connected to power symbols) in the schematic don't get renamed when

copied.

So your 'independent' sub-layouts share them and eagle therefore shows

air-wires connecting them.

--

 

Lorenz

 

Hi Lorenz,

In Tom's case I think he is actually intending the copies to be connected and not independant. It looks like this is a bug that I have seen only a couple of times where EAGLE has a bit of a moment and draws air wires for nets that are already connected.

Best Regards,

Rachael