The PSLab hardware project designed in KiCAD, an ECAD tool; doesn’t support collaborative features like Git providing for software projects. As explained in a previous blog post on techniques to help up with project collaboration, this blog post will demonstrate how two developers can work together on the same hardware project.
The difficulties arise as the whole project is in one big schematic file. Editing made by one developer will affect to the editing done by the other developers causing merge conflicts. KiCAD doesn’t compile nicely if the changes were fixed manually most of the cases.
The solution practiced in the pslab-hardware project is using hierarchical blocks. This blog post will use a KiCAD project with an oscillator implementation and a voltage regulator implementation just like the ones in pslab-hardware schematics. To avoid complications in understanding changes in a huge circuit, only these two modules will be implemented separately in the blog.
Initially the project will look like the following figure;
Sheet1 | Sheet2 |
These two hierarchical blocks will be created as different .sch files in the project directory as follows;
Assume two different developers are working on these two different blocks. That is the key concept in collaborating hardware projects in KiCAD. As long as the outer connections (pins) don’t get changed, edits made to one block will have no effect on the other blocks.
Developer 1 decided that the existing power circuit is not efficient for the PSLab device. So he decided to change the circuit in Sheet 1. The circuit before and after modification is shown in the table below.
Sheet 1 (Before) | Sheet 1 (After) |
If we take a look at the git status now, it will be as follows;
From this it is noticeable that neither the main schematic file nor Developer2.sch hasn’t been touched by the edits made to Developer1.sch file. This avoids merge conflicts happening when all the developers are working on the same schematic file.
Resources :
- http://kicad-pcb.org/help/tutorials/#_tutorials_in_english
- https://github.com/fossasia/pslab-hardware
- https://blog.fossasia.org/how-to-collaborate-design-on-hardware-schematics-in-pslab-project/
- https://en.wikipedia.org/wiki/Top-down_and_bottom-up_design