April 11, 2023

KiCAD tips

First two tips from me.

First, use the tilde key on the keyboard to "light up" a trace (or signal or net, or whatever you want to call it). You do not need to click on it first. Just place the mouse over the label of interest and hit the tilde key.

Second, and much much more imporant. How to move around. I have cursed the KiCAD developers, KiCAD, and the ground they walk upon. The left mouse button ought to be a "hand" button that moves the schematic around. It is not. And worse yet, if you go into preferences, it won't even let you make it so. You are forced to use the center button, which violates deeply learned habits I have (I endlessly use the left button out of habit). Not only that, using the center button on a mouse with a wheel for anything other than rolling the wheel is fiddly.

But there is another way to work. Never use anything other than the center button. Use the wheel to zoom in and out. To move around, zoom out, move the mouse to where you want to be, and zoom in again. It works great, but it only took me about 20 hours of continual swearing and frustration before I figured this out.

Tips from AJ

These are from AJ. He generated the schematics for the Entrex using KiCAD. I think this was a great choice. I am just a KiCAD beginner, so he has given me numerous tips. Much of what follows is specific to the Entrex project.

He uses Preferences -- Preferences to change colors, making the background white and the traces grey. He also emphasizes that the Schematic, not the PCB is now the final authority and the schematic now has corrections that are not on the PCB (if I understand him right). Making the background grey makes the pink activated traces more easily visible.

black is to floppy disk controller (never produced)
pink is to interface board
yellow is to the RAM expansion card (he calls it the ram bus)
green is "data bus" - it goes to every board on the backplane
nice green is "keyboard"

The IO board is outside world connectors. There are backplane connectors for a modem board (that we have never seen). And a board for the printer board if I understand right. We also have a mystery connector.

He describes a trick to group a bunch of signals together into "groups" or what he calls "buses".

When you select signals on the schematic then go view the PCB, you also see the signals highlighted. The signal names in boxes or arrows are global links. Just a name next to a line is local.

Feedback? Questions? Drop me a line!

Tom's Computer Info / tom@mmto.org