I am a new user of orcadpcb and would like to know if it is possible to minimize the length of the ratsnest during the placement of a component and not after it is placed.
place the component near to near so you can reduce the ratsnets
In reply to kabalee:
Yes, but this happens only after the component has been released during the movement ratnest is not updated.
In reply to PcbAG:
The tools don't work this way. The ratsnest is not dynamic. It will only update once you place the part down. You could assign a FUNCKEY to place the part down and pick it back up again which will update the ratsnest connections. Edit your env file to include
funckey " " "pick_to_grid -cursor;pick_to_grid -cursor"
This uses the spacebar to put the part down then pick it up again.
In reply to steve:
Thank you for your answer.I'm surprised.... even the cheaper cads have this function
In reply to RaylonS:
The ratsnest in Allegro is not dynamic. The older Layout product had a dynamic ratsnest, cadence are a bit behind in this respect.
There are settings that can help a little.
Click Setup > Design Parameters on the tool bar. In the dialog box set the ratsnest geometry to Straight. You can also set the ratsnest points to either closest endpoint or pin to pin. Closest enpoint works pretty good.
Other things you can do to make life easier is assign colors to specific nets like ground and power, Disable a ratsnest from showing, Blank all ratsnests so when you move a part only those nets show up.
Hope that helps some
In reply to ScottCad:
In reply to DonlAZ:
You can toggle the stretch etch in the Options tab. This will turn on and off the ratsnets while moving a part.
EMA Design Automation
Make sure they are turned on (Display - Show Rats - All) then invoke the command Edit - Move and make sure that Stretch Etch is not checked (Options fold out menu on the right hand side). If it is the rats become invisible when moving a part.
I am struggling with the rat lines as well but in my situation the "Closest endpoint" setting is not functioning properly. I opened a case over 17 months ago and I was told this is the way the tool is designed to work.
For instance when I finish a route and exit the command I see the rat line extend across the design to a pin to my plating bar when I have a via 100 microns in front of the end point of the route. I just opened another case since this is a later release and I am told the tool functions as designed and nobody else has asked for an enhancement.
I remember back in the day when User Groups were strong and the users would all have a presence to openly discuss issues with the tools in front of the developers. I miss those days because other vendors were responsive to those open forums.
There are many tools on the market both cheaper and more expensive that have the ability to show the rat lines from a route to any of the closest end point (i.e. via, pin, bond finger, etc.) that provide the designer a very helpful guide to plan accordingly at a glance where to route and how to get there in the path of least resistance. I do not have that using this tool and feel like I am not being heard that this is indeed a problem.
Anyone else have this problem?
In reply to tonyhuffman:
unfortunately also I have the same problem. The Ratsnets not close to end point !
I need to swap some pins on a BGA with a PCB Designer Professional, but ratsnest not close to end points of partial routes to pins ! It's a very problem.
Please Cadence resolve this ! There is not a problem for a big factory like CADENCE to solve this, and to add "dynamic" ratsnest minimizations !
Hope some Cadence engineer ear this help request !
Best Regards, Gianni.
In options select Ripup Etch, this will show rats while moving part.
In reply to ChandM:
thank you very much for you reply. Any suggestion are always welcome.
The "Ripup Etch" are not always the desiderable option.
With "Ripup Etch" enabled the reconnect are made only after the place of symbol.
The very desiderable action is, to have a "dynamic reconnect" with attaching the Ratenest to nearest point available, BEFORE you place the symbol.
Others competitors have this :-( Please Cadence make this feature !
Best regards, Gianni.
In reply to GP studio:
For many many many years now I have used tools (late 1980's) that have a dynamic rats nest as you move the part you are intending to place. Moving to a new tool (Cadence) took away this valuable feature that Cadence does not believe brings value. They tell me that it works just fine to show the closest connect point with I strongly beg to differ on that statement.
A connect point can be a component pin, a via or a trace end (partially routed trace that is dangling) but this is not seen as valid points by the Cadence team. This would be so valuable aid when trying to do a quick placement of parts. One day maybe but perhaps one day too late.
your comment describe accurately, waht are need, for "dynamic rats nets".
I hope to Cadence consider this really important, because are a "basic" most important feature.