Comment by tofof | Hacker News Reader

Comment by tofof | Hacker News Reader

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The pinout for the Arduino Due is wrong. The pdf indicates the pin nearest to the reset button (top right on the board, page 124 digital / 122 printed) is D21/SCL.

It is not. That is pin D71, SCL1 (emphasis on the 1) - the Due has two indepdendent i2c busses. It makes a similar error regarding pin D70, just below it.

It also fails to note that D10 = D77 and D4 = D87, and that both of those pins (in addition to D2, D3, D4, D5, D11, D12) support PWM. Frankly the listing of the PWM column is confusing, in general, for the Due, with what is labelled and what isn't.

Contrast: https://forum.arduino.cc/t/due-pinout-diagram/129258

Admittedly, these are carrying forward errors in the official documentation, but these errors have been known for a very long time (they were updated in the unofficial pinout I link in 2013).

Unfortunately, offering only a monochrome (yet unprintable) view, leaving pins (connectors in the center of the board) unlabeled, and carrying errors forward means I don't see a particular use for this document.

  > The pinout for the Arduino Due is wrong.

Lol. Once a famous man said

  > Once you realize that documentation should be laughed at, peed upon, put on fire, and just ridiculed in general, THEN, and only then, have you reached the level where you can safely read it and try to use it to actually implement a driver.

Sounds like a Linus Torvalds qoute.

And he is not wrong

Indeed it is:

>

> It works perfectly and exactly as it is defined to work by the rules.

> Getting the rules correct == 'the concept of "working"'.

Don't be silly.

You're entirely ignoring the concept of hardware bugs. Which is one very likely reason for this whole discussion in the first place.

ANYBODY who does driver development without taking the real world into account is a dangerous person. Stacks of papers, diagrams and rules are absolutely WORTHLESS if you can't just understand the fact that documentation is nothing more than a guide-line.

Once you realize that documentation should be laughed at, peed upon, put on fire, and just ridiculed in general, THEN, and only then, have you reached the level where you can safely read it and try to use it to actually implement a driver.

I'm continually amazed and absolutely scared silly by your blind trust in paperwork, whether it be standards or committees or vendor documentation.

  Linus

https://lwn.net/2001/0118/a/lt-documentation.php3

There's also a nasty gotcha in the Pi Pico pinout. Pins 1-20 are listed from top to bottom, in the same order they appear in the board image. Pins 21-40 are listed in a second column, also from top to bottom; unfortunately, this is the reverse of their physical position in the board image.

Welcome to why those of us who build PCBs NEVER use a parts library other than our own.

Nobody will ever take the care to maintain a parts library unless there is money involved.

The KiCAD libraries are about as good as it gets as long as you stick with common parts.

I never understood this mentality myself. I use parts libraries all the time.

Whether or not I drew the symbol, I still have to double check it as it's not like every symbol I every drew comes out perfectly the first time. So if I need to check it, why not save myself the step of drawing the rough draft of it?

For example I've never had an issue with a snapeda schematic symbol. Even free tier. Although sometimes I rearrange them for esthetic reasons. I've definitely had to adjust their footprints for DFM reasons. But IMHO it's much faster to tweak someone else's work than start from scratch.

Ha! I remember a somewhat similar issue with the Arduino Nano where one pin was erroneously marked as PWM and one not. A customer had designed electric motor drivers controlled by a socketed Nano and I was tasked with writing software for it. They never looked at the actual ATmega pinouts but used the one available on various hobbyist sites all over the net. I ended up cutting traces and soldering jumper wires on the first batch of devices.

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