Header holes on PIM447 Trackball Breakout slightly staggered?

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1

Going by user photos, the offsets are not enough to prevent soldering a 5-pin header in place, but curious why the holes are NOT in perfect alignment, but instead slightly “sawtoothed”? Pins 2 & 4 (SDA & INT) are noticeably farther from the edge than the other 3 pins.

2

It means they’re slightly press-fit. Not enough to avoid soldering altogether, but as a short temporary thing it can work, and it can also make soldering easier as the pins hold themselves in the header while you do it. There are a few different Pimoroni products with that kind of staggering.

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3

What he said, makes soldering easier as it stays in place.

4

OK, thanks… never had an issue with that, but it makes sense.

Might end up plugging this trackball right onto the back of my Pi 400, since the pinout matches GPIO 1-3-5-7-9…

5

I have one on my Pi 400. I have a Pi 400 Flat Hat hacker Plugged in.
The Trackball is on a Proto Zero that plugs into the Hat.
I put an RV3028 beside the trackball, I had room so why not.
I dig my camera out and post a picture latter on.

6

This is what i ended up with mounting my trackball. Looks like I need to get the vacuum out and clean up some cat hair.

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7

This pin alignment (or better misalignment) is the breakout-garden magic. I was actually searching on Pimoroni’s site for an exact spec, but did not find anything. I wanted to use it for some of my own PCBs. I ended up needing three tries until I managed to get the offsets right.

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Ooh, any chance you could share? Pimoroni don’t usually release PCB designs so I imagine releasing the staggering design didn’t occur to them.

9

Here are three PCBs I made:

The first one is a small PCB that adds an I2C connector. The second one is a RTC+I2C connector. The third is a power-control PCB. You can plug the latter two underneath the pico.