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There have been a lot of comments here but I want to leave one specifically to the person or team who designed the Pi’s circuitry: Thank you for working on suc

There have been a lot of comments here but I want to leave one specifically to the person or team who designed the Pi’s circuitry: Thank you for working on such an important project and thank you for all the things that you got right. I’m sure that somewhere, someone is feeling a little bit embarrassed and possibly somewhat sheepish over this and… Please don’t let one incident overshadow all the great things that have come from the existence of the Raspberry Pi!

jaclaz 7y ago
I would add - for what it may count - that IMHO there is an issue with the actual USB-C "standard" (not unlike many other standards that have been made by this or that "technical committee" into a large mass of mostly unreadable stuff). The document (that you can find here [0]) is a 27 Mb .zip [0] https://www.usb.org/document-library/usb-type-ctm-cable-and-connector-specification-revision-14-march-29-2019 https://www.usb.org/document-library/usb-type-ctm-cable-and-... inside there are various .pdf files, the most interesting is the one named "USB Type-C Specification Release 1.4 - Redline from 1.3.pdf" , besides highlighting the changes, some minor like changing "existing" to "legacy USB", it makes clear that the matter is complex. The specification, remember only for USB-C connector and cable, is 338 pages, I wouldn't be so hard with someone that missed something in them.
- LaughingMan11 7y ago
  It's one thing if an enthusiast made a mistake putting together a one-off breadboard for a board they're hacking on. But it's entirely a different problem if a professional engineering organization, with a hardware release process, a factory build process, and a QA process didn't read the spec properly and didn't catch this bug. If it's someone's profession to do engineering, don't give them a pass for not being able to follow an industry specification. Engineering is all about following arcane rules in various specs. If it's not USB, then it's Wifi or Bluetooth, or whathaveyou specs, which are all similarly complicated. For what it's worth, the USB spec is complicated, but in this case, there's actually a picture in the USB Type-C Spec you linked to which tells hardware designers exactly how to put together this circuit. They should have just copied it directly instead of going off-script. I wrote about it here, and included the figure from the spec: https://medium.com/@leung.benson/how-to-design-a-proper-usb-c-power-sink-hint-not-the-way-raspberry-pi-4-did-it-f470d7a5910 https://medium.com/@leung.benson/how-to-design-a-proper-usb-...
  - jaclaz 7y ago
    Hey, you are "the" Benson Leung! I still believe that an error like that one is something that can happen (unlike a number of errors/mistakes you happened to find/highlight over the years). I am not saying that it's "normal", only saying that I can understand how someone could miss this aspect. Engineering is not (or should not be) "following arcane rules in various specs", good engineering is making things as simple as possible (but not simpler) and have them working. The engineer failed in the specific design, but IMHO the whole set of engineers that wrote the USB standard failed in making things simple enough. If we take another (unfortunately) "common" standard (one with which you are not maybe so familiar with) UEFI, its specs are more (last time I checked) than 2200 pages, is it so surprising that its implementation in many boards is not fully-fully compliant to them?
mytailorisrich 7y ago
I've just received my Raspberry Pi 4 with 4GB. For someone who grew up in the 80s and played with computers at the time, this is science fiction that you can actually touch and hold in your hand. (and the manufacturing quality is flawless...)
jchw 7y ago
Yeah, this issue is not a big deal imo. It is an inconvenience, that may piss people off, but it is not a showstopper. I’m sure a minor revision will be made and most of us will not even remember this. I hope this issue doesn’t delay preorders, because I don’t even care if my unit has this issue.
- cesarb 7y ago
  > Yeah, this issue is not a big deal imo. It's not a big deal once they add to their list of "known issues" or "errata", together with the relevant workarounds. Otherwise, they might get too many returns from people who can't get it to power up with any of the chargers they have (because all they have is high-end chargers with 5A cables).
- hermitdev 7y ago
  Seems to me this "fail off" scenario is far better than reports of cheap USB-C cables frying devices. I'd certainly prefer a fail off scenario than fail to frying the attached device and possibly the other, more expensive computer the other end is potentially plugged into.

jaclaz 7y ago

I would add - for what it may count - that IMHO there is an issue with the actual USB-C "standard" (not unlike many other standards that have been made by this or that "technical committee" into a large mass of mostly unreadable stuff). The document (that you can find here [0]) is a 27 Mb .zip [0] https://www.usb.org/document-library/usb-type-ctm-cable-and-connector-specification-revision-14-march-29-2019 https://www.usb.org/document-library/usb-type-ctm-cable-and-... inside there are various .pdf files, the most interesting is the one named "USB Type-C Specification Release 1.4 - Redline from 1.3.pdf" , besides highlighting the changes, some minor like changing "existing" to "legacy USB", it makes clear that the matter is complex. The specification, remember only for USB-C connector and cable, is 338 pages, I wouldn't be so hard with someone that missed something in them.

LaughingMan11 7y ago
It's one thing if an enthusiast made a mistake putting together a one-off breadboard for a board they're hacking on. But it's entirely a different problem if a professional engineering organization, with a hardware release process, a factory build process, and a QA process didn't read the spec properly and didn't catch this bug. If it's someone's profession to do engineering, don't give them a pass for not being able to follow an industry specification. Engineering is all about following arcane rules in various specs. If it's not USB, then it's Wifi or Bluetooth, or whathaveyou specs, which are all similarly complicated. For what it's worth, the USB spec is complicated, but in this case, there's actually a picture in the USB Type-C Spec you linked to which tells hardware designers exactly how to put together this circuit. They should have just copied it directly instead of going off-script. I wrote about it here, and included the figure from the spec: https://medium.com/@leung.benson/how-to-design-a-proper-usb-c-power-sink-hint-not-the-way-raspberry-pi-4-did-it-f470d7a5910 https://medium.com/@leung.benson/how-to-design-a-proper-usb-...
- jaclaz 7y ago
  Hey, you are "the" Benson Leung! I still believe that an error like that one is something that can happen (unlike a number of errors/mistakes you happened to find/highlight over the years). I am not saying that it's "normal", only saying that I can understand how someone could miss this aspect. Engineering is not (or should not be) "following arcane rules in various specs", good engineering is making things as simple as possible (but not simpler) and have them working. The engineer failed in the specific design, but IMHO the whole set of engineers that wrote the USB standard failed in making things simple enough. If we take another (unfortunately) "common" standard (one with which you are not maybe so familiar with) UEFI, its specs are more (last time I checked) than 2200 pages, is it so surprising that its implementation in many boards is not fully-fully compliant to them?

mytailorisrich 7y ago

I've just received my Raspberry Pi 4 with 4GB. For someone who grew up in the 80s and played with computers at the time, this is science fiction that you can actually touch and hold in your hand. (and the manufacturing quality is flawless...)

jchw 7y ago

Yeah, this issue is not a big deal imo. It is an inconvenience, that may piss people off, but it is not a showstopper. I’m sure a minor revision will be made and most of us will not even remember this. I hope this issue doesn’t delay preorders, because I don’t even care if my unit has this issue.

cesarb 7y ago
> Yeah, this issue is not a big deal imo. It's not a big deal once they add to their list of "known issues" or "errata", together with the relevant workarounds. Otherwise, they might get too many returns from people who can't get it to power up with any of the chargers they have (because all they have is high-end chargers with 5A cables).
hermitdev 7y ago
Seems to me this "fail off" scenario is far better than reports of cheap USB-C cables frying devices. I'd certainly prefer a fail off scenario than fail to frying the attached device and possibly the other, more expensive computer the other end is potentially plugged into.