I’m still learning so my apologies if this is answered some place else. I’ve looked but didn’t find it.
I have a circuit that was breadboarded, then turned into a schematic and then I created the PCB layout from it.
Like anything else, I fiddled with the PCB design to see what happens. But, now I want to wipe the fiddled version, and remove all the changes I created and let the PCB design subsystem start again with a clean slate.
I’m not sure how to do this. Anyone got a suggestion?
It seems like I should be able to do something simple like “erase the pcb” and put a new blank into place then ask it to run the parts layout and routing all again. I just can’t sort out how yet.
I don’t think there is auto placement, is there?
In any case, you cannot “erase the PCB”. The three views are connected. If you remove a part from one view (PCB) it also deleted from the others. It is all one circuit, just three different views.
What you can do, is delete all the traces in the PCB view, and then let the autorouter run again. For that, select Routing->Select All Traces and then Edit->Delete.
To remove all the traces in pcb click Routing and then select all traces, then hit the delete key. That will erase all the traces leaving you with the rats nest lines from the other two views. Click on a rats nest line to create the trace, then move it to be routed how you wish (clicking on the rats nest line will connect the trace to the right place according to Fritzing.)
Clearing the traces isn’t the issue. Resetting the component placement is.
If I create a new project, breadboard a dozen components, generate a schematic then go to the PCB tab, a board with the components laid out is presented.
This tells me, that at some point, there was an initial layout (and decisions) about board size and locations made. Right, wrong, optimized or not, there was a state 0 point in the design process.
I’d like to wipe out all subsequent fiddling and go back to that state without wiping the project and recreating it from scratch.
There is a default (initial) size for the pcb board, to place parts on. It can not be ‘restored to default’, but if you record the initial dimension, they can be changed back at any time. That seems to be 84.7 by 56.6 mm.
The part layout though is very arbitrary. I have never figured out what rules Frtizing uses to set the initial position of a part on one view, when it is placed in a different view. They can be widely spaced, needing multiple zoom out operations, or fit to window, to find where they landed. In other cases, the parts are directly on top of each other, needing to be dragged apart to see which one is which.
There is no way to go back to the that initial placement layout in a view. The closest you could come, is to save a copy of the sketch after breadboard and schematic are done, and before starting on the pcb view. Then go back to that saved copy at a later time, which would also undo any changes that had been made to the other views.
i have never found that initial layout to be useful. I always start by dragging the outlying parts in close, and unstacking the overlapping parts as the first step, before trying to do any sort of real layout.
As @microMerlin said, initial parts placement is a mess. The first thing I do is move the parts in to some reasonable order in all three views, then save a copy of the .fzz file (without any connections routed in any view.) If you find later that a different layout makes routing easier (my typical reason for moving parts around) reload the initial .fzz file, make the part location changes in that and save it as a new .fzz file (so you can go back to the original if you need to later.) then do the routing. It is also a good practice to do one view breadboard or schematic usually) completely first, then use the rats nest lines to route the traces in the other two views. If you make changes in another view, and make them wrong, you can corrupt the routing database (although I have never been able to reproduce the steps to cause the corruption which may let us fix it!) and have to clear all the traces and start again.