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Comment by pi-rat | Hacker News Reader

Not for people with OCD, that's an interesting board layout :)

I dread to think how long it took to lay that out, but I'm pretty impressed. A lesser person would have just given up and used a larger PCB, but they were clearly determined to fit everything in the same footprint as a Raspberry PI.

It may have been routed with https://en.wikipedia.org/wiki/TopoR

That was my thought as well, but the traces don't look like TopoR traces.

Huh. That's... actually quite interesting.

Is there a reason for the odd layout? Some pathalogical issue with utoplacement doing the best it can to fit components into a limited space? Trying to avoid sharp edges in the track for some weird capacitance reason? Or maybe it's deliberate to try and drive its users insane... anyone actually know?

45° rotation make sense when you want to avoid having half of your traces exit a dense chip towards the board edges, assuming (which often is the case) a rectangular board.

I guess in this particular case, the (many, and sensitive to total length and relative length with respect to each other) traces connecting CPU and RAM had been routed in isolation first. These chips seem to be 45° rotates against each other.

Then the group of CPU & RAM had been rotated too leave enough space for power/camera/HDMI, I'd guess.

It looks strange, but frankly there is no real reason (besides aesthetics) to favor any particular orientation.

It seems a sensible one. Why should components be aligned to 90 degree angles, when higgledy-piggledy might pack them in a smaller space?

I've worked with a PCB layout designer, and one comment he made is that it's far easier to do a 'by eye' check of, firstly, the virtual layout in CAD, and then the assembled board when things are arranged neatly or at 'nice angles'. Having done some PCB layout myself - mostly through-hole, although with a large number of parts - I never found circumstances in which odd angles made it easier to do the layout. However, I concede it might be for reasons of short traces or making traces certain lengths if required for timing reasons.

Yeah I was thinking the same thing. I imagine finding a part on that board by reference designator is hard.

I can't imagine turning in a schematic drawn like that (parts rotated) for a test in college.

Those with OCD would need to also buy a non-transparent case for their developer board :-).

Must be alien technology. :)

The thing that got me was it blue!

If you like that, you'll love oshpark's deep purple soldermask colour.

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