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posted by martyb on Wednesday July 10 2019, @04:04AM   Printer-friendly
from the so-much-for-port-a-bility dept.

Raspberry Pi admits to faulty USB-C design on the Pi 4

The Raspberry Pi 4 was announced two weeks ago as a major new upgrade to the line of cheap single-board hobbyist computers. The Pi 4 featured a faster CPU, options for up to 4GB of RAM, and a new, modern USB-C port for power delivery. The Pi 4 was the Raspberry Pi Foundation's first ever USB-C device, and, well, they screwed it up.

As detailed by Tyler Ward, the Raspberry Pi 4 has a non-compliant USB-C charging port and doesn't work with as many chargers as it should. Thanks to the open nature of Raspberry Pi (even the schematics are online!), Ward was able to discover that Raspberry Pi just didn't design its USB-C port correctly. Two "CC" pins on a USB-C port are supposed to each get their own 5.1K ohms resistor, but Raspberry Pi came up with its own circuit design that allows them to share a single resistor. This is not a compliant design and breaks compatibility with some of the more powerful USB-C chargers out there.

[...] The Pi 4 is not the first high-profile device to get the USB-C spec wrong. The Nintendo Switch also has a non-compliant USB-C port and has issues with certain USB-C cables as a result.

After reports started popping up on the Internet, Raspberry Pi cofounder Eben Upton admitted to TechRepublic that "A smart charger with an e-marked cable will incorrectly identify the Raspberry Pi 4 as an audio adapter accessory and refuse to provide power." Upton went on to say, "I expect this will be fixed in a future board revision, but for now users will need to apply one of the suggested workarounds. It's surprising this didn't show up in our (quite extensive) field testing program."

Probably not a dealbreaker (the cables that do work are cheaper), but could be annoying.

Previously: Raspberry Pi 4 Model B Launched


Original Submission

Related Stories

Raspberry Pi 4 Model B Launched 46 comments

The Raspberry Pi 4 Model B has been launched, despite months of tricky misdirection implying that it wouldn't be on the market until 2020. The technical specifications include two micro HDMI ports, two USB3 ports, two USB2 ports, dual band Wi-fi, Bluetooth 5, Gigabit Ethernet, and either 1GB, 2GB, or 4GB of RAM. Power consumption is noticeably higher than similar earlier models and the power can be supplied over USBC.

From the spec sheet:

  • Broadcom BCM2711, Quad core Cortex-A72 (ARM v8) 64-bit SoC @ 1.5GHz
  • 1GB ($35), 2GB ($45), or 4GB LPDDR4-2400 SDRAM ($55)
  • 2.4 GHz and 5.0 GHz IEEE 802.11ac wireless, Bluetooth 5.0, BLE
  • Gigabit Ethernet
  • 2 USB 3.0 ports; 2 USB 2.0 ports.
  • Raspberry Pi standard 40 pin GPIO header (fully backwards compatible with previous boards)
  • 2 × micro-HDMI ports (up to 4kp60 supported)
  • 2-lane MIPI DSI display port
  • 2-lane MIPI CSI camera port
  • 4-pole stereo audio and composite video port
  • H.265 (4kp60 decode), H264 (1080p60 decode, 1080p30 encode)
  • OpenGL ES 3.0 graphics
  • Micro-SD card slot for loading operating system and data storage
  • 5V DC via USB-C connector (minimum 3A*)
  • 5V DC via GPIO header (minimum 3A*)
  • Power over Ethernet (PoE) enabled (requires separate PoE HAT)
  • Operating temperature: 0 – 50 degrees C ambient

takyon: Review at Tom's Hardware. Cons: "Key software doesn't work at launch, Poor high-res video playback". Cases for the previous Pi don't work due to the new micro-HDMI ports. Tom's measured nearly ten times better storage performance using one of the new USB 3.0 ports, and the gigabit Ethernet port can actually reach nearly 1 Gbps (943 Mbps vs. 237 Mbps for the previous model).

Also at The Verge and Ars Technica.


Original Submission #1Original Submission #2Original Submission #3

Raspberry Pi 4B CPU Overclocked to 2.147 GHz, GPU at 750 MHz 41 comments

Raspberry Pi 4 Can Now Overclock to 2.147 GHz. Here's How.

The Raspberry Pi 4 is much faster than every prior Raspberry Pi, but what if you could squeeze much more than the base 1.5 GHz out of its Broadcom BCM2711B0 CPU? Fortunately, it's easy to overclock any Raspberry Pi and you can do it just by tweaking a few lines of text in the /boot/config.txt file. Now, with the latest firmware, we were able to reach a speed of 2,147 MHz, which we believe is a new high.

With prior firmware, the Pi 4 B's processor was limited to a maximum overclocked frequency of 2 GHz, which is pretty good all by itself. However, the latest update let us push it up another 147 MHz. We were also able to increase the GPU clock speed to 750 MHz, a big boost over its 500 MHz stock speed and the 600 MHz we had overclocked it to previously.

Before 2 GHz, the max overclock was 1.75 GHz with the original, stable firmware.

Also at Electronics Weekly.

Previously: Raspberry Pi 4 Model B Launched
Raspberry Pi 4 Has a Non-Compliant USB-C Charging Port
Too Hot to Handle? Raspberry Pi 4 Fans Left Wondering If Kit Should Come With a Heatsink


Original Submission

2 GB Model of Raspberry Pi 4 Gets Permanent Price Cut to $35 13 comments

A birthday gift: 2GB Raspberry Pi 4 now only $35

In two days' time, it will be our eighth birthday (or our second, depending on your point of view). Many of you set your alarms and got up early on the morning of 29 February 2012, to order your Raspberry Pi from our newly minted licensee partners, RS Components and Premier Farnell. In the years since, we've sold over 30 million Raspberry Pi computers; we've seen our products used in an incredible range of applications all over the world (and occasionally off it); and we've found our own place in a community of makers, hobbyists, engineers and educators who are changing the world, one project, or one student, at a time.

[...] Which brings us to today's announcement. The fall in RAM prices over the last year has allowed us to cut the price of the 2GB variant of Raspberry Pi 4 to $35. Effective immediately, you will be able to buy a no-compromises desktop PC for the same price as Raspberry Pi 1 in 2012. [...] And of course, thanks to inflation, $35 in 2012 is equivalent to nearly $40 today. So effectively you're getting all these improvements, and a $5 price cut.

[...] In line with our commitment to long-term support, the 1GB product will remain available to industrial and commercial customers, at a list price of $35. As there is no price advantage over the 2GB product, we expect most users to opt for the larger-memory variant. [...] The 4GB variant of Raspberry Pi 4 will remain on sale, priced at $55.

In addition to falling RAM prices (which will hopefully continue to fall in the future), there is likely an oversupply of the 2 GB model as the 4 GB model proved to be the most popular.

Also at TechCrunch, Tom's Hardware, PCWorld, and Hackaday.

The USB Type-C resistor issue has been fixed by the latest revision of the Raspberry Pi 4 Model B hardware, which is confirmed to be out in the wild. The issue prevented some USB-C power supplies from working with Pi4B:

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  • (Score: 0) by Anonymous Coward on Wednesday July 10 2019, @04:46AM (25 children)

    by Anonymous Coward on Wednesday July 10 2019, @04:46AM (#865285)

    Don't know why they had been using USB hardware all this time, I would prefer to power them with a barrel connector.

    • (Score: 2) by takyon on Wednesday July 10 2019, @05:17AM (1 child)

      by takyon (881) <reversethis-{gro ... s} {ta} {noykat}> on Wednesday July 10 2019, @05:17AM (#865289) Journal

      Pretty much all phones are using Micro-USB or USB-C to charge, so there are a lot of cables around and they are easy to get.

      --
      [SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
      • (Score: 0) by Anonymous Coward on Wednesday July 10 2019, @07:33PM

        by Anonymous Coward on Wednesday July 10 2019, @07:33PM (#865473)

        Also Europe requires standardisation of charging ports. True RPi did not have meet that standard, but you are right there are a lot of micro-b usb-c charges now, becuase of Europe's requirement.

        IE: Less waste.

    • (Score: 5, Interesting) by deimios on Wednesday July 10 2019, @05:18AM

      by deimios (201) Subscriber Badge on Wednesday July 10 2019, @05:18AM (#865290) Journal

      There are some advantages like:

      Compatibility: Slap it on the back of a TV and just give it power from the 1 amp USB port directly from the TV.
      Convenience: Just use a spare phone charger to power it, even if you lose the original charger.

      Of course it has problems too as TFS explains. Heck back in the RasPi v1 days it was nigh impossible to get a decent charger that could supply the power for overclocking. I had to use a powered usb hub.

    • (Score: 2) by RS3 on Wednesday July 10 2019, @05:56AM (4 children)

      by RS3 (6367) on Wednesday July 10 2019, @05:56AM (#865292)

      "Barrel connector"?? Do you mean one of the too many types and sizes of little power connectors on most small electronics? You could cobble one on. I'd probably solder wires to the Pi and the connector to them- make a little dongle.

      • (Score: 3, Interesting) by c0lo on Wednesday July 10 2019, @06:09AM (3 children)

        by c0lo (156) Subscriber Badge on Wednesday July 10 2019, @06:09AM (#865296) Journal

        Do you mean one of the too many types and sizes of little power connectors on most small electronics?

        At least some RapPies models can accommodate to power delivered over GPIO but is not regulated on-board [thepihut.com], you need deal with the issue yourself. Get a cheap and crappy wallwart and you can place a RIP sign on your RasPi.

        (in contrast with Arduino boards, where they can accept input voltages in a range)

        --
        https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
        • (Score: 2) by RS3 on Wednesday July 10 2019, @01:22PM (2 children)

          by RS3 (6367) on Wednesday July 10 2019, @01:22PM (#865364)

          Yes and no.

          True there's no voltage regulation onboard, but there's an overvolt protector SMBJ5.0A-TR https://www.st.com/resource/en/datasheet/smbj.pdf [st.com] that might save it unless a person is really determined to be stupid, in which case they'll learn a very basic electronics lesson, and hopefully learn a big-picture lesson about taking action without knowing what you're doing, aka: overconfident. (And no, I've never done anything like that. /s )

          Yes you should only power the Pi with a 5 VDC regulated supply, and many wallwarts / linelumps / power bricks are 5 V regulated.

          And it doesn't need to be a "cheap and crappy" wallwart- a good expensive 30 V 5 A one would kill a Pi. Heck, 9 or 12 V ones would if they can supply enough amps to overpower the overvolt protector. I'd have put a low-value resistor and self-resetting fuse in series with the 5 V coming in, before the SMBJ5.0A-TR.

          I'd recommend a regulator on the Pi and pads for my power dongle idea. So many sources of 12 - 18 V available these days, and so simple to do, why not.

          • (Score: 0) by Anonymous Coward on Wednesday July 10 2019, @02:38PM (1 child)

            by Anonymous Coward on Wednesday July 10 2019, @02:38PM (#865385)

            Transient voltage suppressors like that are designed to suppress, well, transients. They are not designed to continually dump power from an out-of-spec power supply. If you did connect such a supply the TVS device is likely to fail very quickly, probably quite spectacularly too.

            • (Score: 3, Informative) by RS3 on Wednesday July 10 2019, @02:53PM

              by RS3 (6367) on Wednesday July 10 2019, @02:53PM (#865387)

              Which is why I said I would design in a series resistor and self-resetting fuse.

    • (Score: 2, Interesting) by driverless on Wednesday July 10 2019, @05:58AM (4 children)

      by driverless (4770) on Wednesday July 10 2019, @05:58AM (#865293)

      It's not just that, the Pi's have been full of hardware design flaws since the very first one (no real power protection circuitry, no proper USB protection circuitry, backpowering the Pi by plugging in a USB device, ethernet-over-USB, the list goes on and on, and some of it is the most basic stuff, just copy the sample circuit from the manufacturer's data sheet). You'd think that by version 4 they'd have finally got good designers to work on it, but it seems every time they fix up one mistake they add two more.

      • (Score: 5, Informative) by Booga1 on Wednesday July 10 2019, @10:40AM (1 child)

        by Booga1 (6333) on Wednesday July 10 2019, @10:40AM (#865333)

        I know you refer to them as flaws, but from their perspective I'm sure they were tradeoffs. When they announced they were going to make a whole computer for $25 people said it couldn't be done, not at that price at least.
        They got it made at the promised cost and achieved far more than many expected. Now there's models for $5 and even the latest ones at highest spec are only $55.

        Every time I look at any of the other similar low cost boards I see a lot of similar trade off decisions made. If they gave in to everyone's favorite pet peeve, it'd be $4 more for an eMMC slot, $3 more for some on-board EPROM, $5 more for supporting full size dual-HDMI ports, and so on until the product costs another 30-50% more or higher.

        They're not perfect, but for what they are they seem pretty reasonable to me. They're also not the only micro-PC maker any more.
        If you need something that the Raspberry Pi doesn't do there's probably an ODROID, Arduino, or other board that does. The choices are getting better every time I look.

        • (Score: 4, Interesting) by driverless on Wednesday July 10 2019, @11:27PM

          by driverless (4770) on Wednesday July 10 2019, @11:27PM (#865554)

          I know you refer to them as flaws, but from their perspective I'm sure they were tradeoffs.

          I don't think they're conscious tradeoffs, some like the USB-ethernet bridge may be, but a lot of others are just bad design. Look at one of the Pi's most notorious problems, its habit of trashing its firmware. The standard response to this is "you've used a bad SD card", and that's certainly true for a percentage of users who go with the cheapest Chinesium SD cards you can get, but it doesn't hold when you're using something like a Samsung EVO and it still trashes its firmware. For that, you have to look at the design: Cheap cellphone charger and micro USB port instead of a proper power supply and barrel jack connector, little to no power control/conditioning (unless they've fixed this in the 4), an SD card instead of eMMC, and a filesystem that's totally wrong for flash. It's wrong piled on wrong piled on wrong. Every single Pi I've ever worked with has trashed its firmware at least once, in same cases several times. Every single non-Pi I've worked with has never trashed its firmware, because the hardware was designed properly. If you compare the Pi to something like an Odroid, it's like an anti-Pi, the hardware is done right and it costs only a little more than a Pi (depending on spec). Unless your time is free (mine isn't), I'll pay a bit more and know that the device I'm using won't need constant coddling and nursing just to keep them running.

          Then there's the incidental costs. Sure, you can get a Pi for $little, but then I've had to spend more than the cost of the Pi to add a Pi-compatible power supply, a Pi-compatible USB hub, and a pile of other crap that's needed to compensate for the Pi's bad hardware design. I'm happy to pay a massive $10 more for something that isn't a Pi just to avoid all the Pi-specific crap you have to go through to get it running and keep it running. Heck, I'd pay double the price of the Pi to get something reliable, although I don't really need to do that because Pi competitors are roughly in the same price range, but properly designed.

      • (Score: 3, Interesting) by RS3 on Wednesday July 10 2019, @01:27PM

        by RS3 (6367) on Wednesday July 10 2019, @01:27PM (#865366)

        You are spot-on, IMHO. I'm often stunned by how bad some circuit designs are, when the manufacturers give free design guide circuits. Just copy the circuit, maybe tweak some values assuming you know what you're doing. It's the original open-source. Transistor and IC spec. books always did / do this.

      • (Score: 2) by DannyB on Wednesday July 10 2019, @01:52PM

        by DannyB (5839) Subscriber Badge on Wednesday July 10 2019, @01:52PM (#865374) Journal

        the Pi's have been full of hardware design flaws since the very first one (no real power protection circuitry, no proper USB protection circuitry, backpowering the Pi by plugging in a USB device, ethernet-over-USB, the list goes on and on

        Because they are designed for children to use.

        --
        The most difficult part of the art of fencing is digging the holes and carrying the fence posts.
    • (Score: 3, Informative) by DannyB on Wednesday July 10 2019, @01:50PM (11 children)

      by DannyB (5839) Subscriber Badge on Wednesday July 10 2019, @01:50PM (#865373) Journal

      I would prefer to power them with a barrel connector.

      <non-sarcasm>
      With a barrel connector there is no way to have a protocol which negotiates the amount of charging power to supply to the device.

      A USB-C phone charger can deliver 15 watts, and a laptop charger can deliver 45 watts. Furthermore, you can use either charger on the wrong device. (eg, laptop charger to charge your phone). If you charge the laptop with the phone charger the laptop (pixelbook in my case) tells you it is charging slowly.
      </non-sarcasm>

      A barrel connector only has two conductors, black and red. Those colors no doubt carry some special meaning which eludes software developers.

      Furthermore with any kind of USB connector, the charger can pretend to be: "hey, I'm not a charger, I'm a USB hub, and connected to me is a keyboard, mouse and a thumb drive; we would like to send you some human input (clicks, keystrokes) to install new fantabulous apps!". Try doing that with a stone knives and bearskins connector.

      --
      The most difficult part of the art of fencing is digging the holes and carrying the fence posts.
      • (Score: 2) by RS3 on Wednesday July 10 2019, @03:03PM (10 children)

        by RS3 (6367) on Wednesday July 10 2019, @03:03PM (#865395)

        I have great respect and admiration for you and your posts, however I'm baffled by this one.

        The Pi circuits need regulated 5 V and they're asking for 3 A minimum. You could connect a 5 V 1,000 A power supply and the Pi will only draw (take) the amps it needs.

        I'm not sure how "charger" comes into play. Maybe a given charger won't deliver the 3 A unless the device it's plugged in to commands it to supply the necessary amps, but then the volts would drop below 5 and the Pi would likely go berserk or just shut down.

        Again, sorry, I'm not following what you're trying to say here, unless that's what you were saying (some chargers need sw commands on the CC pins...)

        • (Score: 3, Interesting) by DannyB on Wednesday July 10 2019, @06:54PM (1 child)

          by DannyB (5839) Subscriber Badge on Wednesday July 10 2019, @06:54PM (#865461) Journal

          I don't now the precise details of USB-C charging. What I think happens is that there is a maximum amount of current, but voltage is increased up to about 18 V after negotiation with the device being charged.

          Doing some googling . . . two sources said: "up to 100 watts"

          One source said: With up to 100 watts, or 3 amps of power, USB-C cables can power almost anything.

          100 watts at 3 amps would mean about 33.333 volts.

          My Pixelbook charger is 45 watts. My third party Amazon charger (spare for pixelbook) is also 45 watts. My Pixel 3 XL phone charger is 15 watts. I have used:
          * third party 45 W charger on Pixelbook
          * pixelbook original 45 W charger on both Pixelbook
          * pixelbook original 45 W charger on Pixel 3 XL Phone -- but it only charges at the phone's fast charge rate -- of 15 watts.
          * Pixel 3 XL Phone charger on Pixelbook -- the pixelbook alerts that it is charging slowly.

          In addition:
          * I have used a USB-C to USB-C cable to connect my phone and pixelbook together.
          Doing this, from both the phone and pixelbook you can select which device will charge another device, and which device will get charged. Yes, the phone can charge the pixelbook from the phone's battery -- but the pixelbook also gives an alert that it is charging slowly

          Now what about a Raspberry Pi?

          If they are cheap enough to use one resistor where they were supposed to use two, I suspect this USB-C port may not implement the charging negotiation spec at all. (Speculation on my part) Therefore, it may be that you must used a 3A 5V USB-C charger with the Pi. I suspect the USB-C port on the PI is voltage regulated, but would it like 33.333 volts?

          --
          The most difficult part of the art of fencing is digging the holes and carrying the fence posts.
          • (Score: 3, Interesting) by RS3 on Thursday July 11 2019, @04:37AM

            by RS3 (6367) on Thursday July 11 2019, @04:37AM (#865679)

            Awesome, thanks. I need to study USB-C more. ... Okay:

            USB Power Delivery uses one of CC1, CC2 pins for power negotiation up to 20 V at 5 A (or whatever less the source can provide). It is transparent to any data transmission mode, and can therefore be used together with any of them.

            - and -

            USB 3.0/3.1/3.2
            In the USB 3.0/3.1/3.2 mode, two or four high speed links are used in TX/RX pairs to provide 5 to 20 Gbit/s throughput. One of the CC pins is used to negotiate the mode.

            VBUS and GND provide 5 V up to 900 mA, in accordance with the USB 3.1 specification. A specific USB-C mode may also be entered, where 5 V up to 3 A is provided.[53] A third alternative is to establish a Power Delivery contract.

            ... which is probably what you referred to, and can be up to 20 V @ 5 A (ouch). Why do I envision some magic-smoke-releasing software bugs? "Hi, I'm Mr. Bill. Yes, please give me 20 V @ 5 A, I can take it! Noooooooo Mr. Billlllllllll!!!!!!" Sorry, I digress.

            The Pi schematic shows they just dead-shorted the CC1 and CC2 pins, which then goes into 2 resistors which feeds "PD_SENSE" which goes into ...

            holy moly- there's a big complex switching regulator on the Pi, which provides 3.3V, 1.8V, 1.1V, Vcore, and a 2nd tiny switcher which provides 1.08V, 1.05V, and 1.0V.

            Okay, that's pretty cool, I'm impressed. I'm betting it's very RFI quiet. Very short copper with ground plane everywhere- should be negligible RFI.

        • (Score: 2) by fyngyrz on Wednesday July 10 2019, @06:56PM (7 children)

          by fyngyrz (6567) on Wednesday July 10 2019, @06:56PM (#865463) Journal

          You could connect a 5 V 1,000 A power supply and the Pi will only draw (take) the amps it needs.

          Since we're doing "here's what I would have done posts"...

          I'd have put a barrel plug (much more robust than these awful USB cables), as well as two heavy PCB holes one could actually solder wires into, followed by a bridge rectifier so power supply polarity was irrelevant, and then popped 1, 2 or 3 five volt linear regulators on there, depending on the current demands of the particular SoC.

          Heat, heat sinks... yep. That's the compromise, but it's a great one.

          Then there'd be a wide range of linear power supplies that would work just fine, and the risk of damaging the hardware comes down to providing (way) too high a DC voltage. Probably would survive an AC adaptor as well, though I doubt it'd get the computer running. 😊. Unless you threw an ultracap on there, but they're pretty bulky at higher voltages, still. You could power it from your car's 12 VDC system and that would work, though you'd want to be extra careful about shutting the car down with the RPi running.

          I've had way, way more than enough of these awful RFI-emitting, short-lifetime el-cheapo switching power supplies, fragile cables, incredibly crappily designed USB plugs (the micro USB plug is what I'm referring to here), and USB female connectors that peel right the hell off the PCB because some lackwit thought that surface mounting them would be sufficient, which it bloody well is not, specifically because those awful USB connectors can't be plugged in both ways, and when an attempt is made to do it wrong (which, strangely enough, seems to be about half the time), it puts serious mechanical stress on the female end's mount, typically with a mechanical advantage incorporating some leverage.

          Don't get me wrong — I still want one of these to fool with, but... yeah, I'd certainly have done it differently.

          --
          The gene pool is shallow. And polluted.

          • (Score: 2) by takyon on Wednesday July 10 2019, @07:42PM

            by takyon (881) <reversethis-{gro ... s} {ta} {noykat}> on Wednesday July 10 2019, @07:42PM (#865475) Journal

            The way I hear it, you already want a heat sink or FLIRC case [flirc.tv] if you are running this thing.

            --
            [SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
          • (Score: 2, Interesting) by Anonymous Coward on Wednesday July 10 2019, @09:17PM (4 children)

            by Anonymous Coward on Wednesday July 10 2019, @09:17PM (#865503)

            I'd have put a barrel plug (much more robust than these awful USB cables), as well as two heavy PCB holes one could actually solder wires into, followed by a bridge rectifier so power supply polarity was irrelevant, and then popped 1, 2 or 3 five volt linear regulators on there, depending on the current demands of the particular SoC.

            I'm glad you're not designing it then...

            Sure we can use 7805 type linear regulators, typically with about a ~2V minimum dropout voltage... Add in the ~1.5V or so drop in the bridge rectifier and we'll need an input voltage of about ~9V, so this power supply, by itself, is consuming almost as much power as the rest of the board combined!

            Let's say we need 15W out of this, 7805 type regulators typically have a max output current of 1A so three are required and together with the bridge rectifier, represents (in volume!) about $1 of extra BOM cost on a device which retails for $35, ignoring whatever cooling upgrades are required for this.

            Using an LDO type regulator can help with efficiency, but usually have much lower power output (and are also much more finicky to use) so this will probably be an even more expensive option. Likewise efficiency of the rectifier can be improved using more intricate designs (-> $$$)...

            • (Score: 3, Funny) by fyngyrz on Wednesday July 10 2019, @10:23PM (1 child)

              by fyngyrz (6567) on Wednesday July 10 2019, @10:23PM (#865533) Journal

              Well, here's the thing. None of your concerns are my concerns. 😊

              --
              Every once in a while declare peace. It confuses your enemies.

              • (Score: 2) by RS3 on Thursday July 11 2019, @03:33AM

                by RS3 (6367) on Thursday July 11 2019, @03:33AM (#865658)

                I know you weren't trying to be funny, but I actually laughed out loud a bit. And it might be because you started with "Well, here's the thing." I generally don't watch and can't stand most sitcoms, but there was this one called "Becker" starring Ted Danson who played a doctor of sorts. His assistant Linda was stunningly ditzy and whenever she did something stupid she'd start her explanation with "here's the thing", and something funny always followed.

            • (Score: 3, Informative) by Knowledge Troll on Thursday July 11 2019, @01:44AM (1 child)

              by Knowledge Troll (5948) on Thursday July 11 2019, @01:44AM (#865603) Homepage Journal

              I'm glad you're not designing it then...

              represents (in volume!) about $1 of extra BOM cost on a device which retails for $35, ignoring whatever cooling upgrades are required for this.

              I'd have gone even further and not tried to cost cut with the linear regulators and go all the way to switching regulators. Switching regulators with 5 volt output, 25 watts power handling capacity, and tolerant of inputs up to 16 volts can be had at retail for less than $4 in the form of r/c aircraft battery eliminator circuits (BEC). That's $4 full retail cost to the end user. To retail at that cost they must have got the entire unit down around $1.

              So lets run with $1 added to the $35 retail price of the RPI: that's a 2.8% increase in cost. That single dollar bought the user not having all these common power delivery issues as well as having the full 5 volts available at the USB ports and also not having to use crappy USB power supplies. Another amazing benefit is that the forums wouldn't be clogged up with people having power issues.

              The poor power regulation was a really bad place to try to cost cut. That has caused a ton of pain for a lot of people.

              • (Score: 0) by Anonymous Coward on Friday July 12 2019, @05:22AM

                by Anonymous Coward on Friday July 12 2019, @05:22AM (#866117)

                I'd have gone even further and not tried to cost cut with the linear regulators and go all the way to switching regulators.

                A switching design would make much more sense for this product but the earlier poster made it quite clear that they did not want to use a switching regulator for EMI reasons (justified or not).

                represents (in volume!) about $1 of extra BOM cost on a device which retails for $35, ignoring whatever cooling upgrades are required for this.

                [...]
                So lets run with $1 added to the $35 retail price of the RPI: that's a 2.8% increase in cost.

                Well this is a non sequitur: a $1 increase in BOM cost does not imply a $1 increase in the retail price of the finished product. I'd guestimate adding onboard regulation without changing anything else would turn this in to a $40 product.

                The poor power regulation was a really bad place to try to cost cut. That has caused a ton of pain for a lot of people.

                I'm not really familiar with this particular product design... However, these issues seem really quite minor, easily worked around and will likely be fixed in the next board revision. So I'd say it remains to be seen whether this was really a bad decision. If you take shortcuts somewhere else instead people will complain about that too: this is just life with products built to a price. If that's a problem one can get products where the designers never make any tradeoffs to save costs...

                What does seem strange to me, however, is that TFA suggests they made a deliberate design decision to reduce the number of 5.1k resistors from two to one, contrary to the USB specification. This essentially does not save anything at all, because resistors often literally cost nothing beyond the reel space (which they've already committed because they still have this resistor value in the design). Judging by the photos it does not look like there would be any real problem fitting another one onto the board...

          • (Score: 2) by RS3 on Thursday July 11 2019, @04:09AM

            by RS3 (6367) on Thursday July 11 2019, @04:09AM (#865669)

            Awesome post- I'm in strong agreement mostly.

            Mounting on a PC board- surface or through-hole- _any_ mechanical connector, switch, button, pot, etc., that humans touch or gets mechanical stress is piss-poor design IMHO. That's why I suggested the dongle for the power connector. I know, I hear it now, it's supposed to be cheap. But you can find connectors with through-hole reinforcements (and even they break easily...)

            My only issue with your post: I would NOT use a diode bridge. Of course I know why you suggested it, but think about the ground (electrical return or common) problem. If you use a bridge, then the car's (or anything's) ground is NOT Pi ground- there's a diode separating the two. I'd just use a single diode to guard against reverse-polarity and that's good enough.

            I'm not against switching supplies, but you make good points about the RFI. They can be shielded, and properly designed so as to minimize / damp out RFI-producing ringing. In fact, for something this small there are some great regulator chips that run with one inductor and minimal RFI.

            As much as I am an analog/linear EE and generally prefer simpler linear regulators, at 3 A drawn, running off a car's electrics would cause a 7805 to dissipate almost 30 watts, and that's not a small heatsink. Oh, and oops- a 7805 is only good for 1.5 A, so a current-passing booster transistor is needed (easy). Still 30 W to unload.

            More research needed...

  • (Score: 1) by shrewdsheep on Wednesday July 10 2019, @09:11AM (8 children)

    by shrewdsheep (5215) on Wednesday July 10 2019, @09:11AM (#865324)

    It's surprising this didn't show up in our (quite extensive) field testing program.

    This is quoting from a clueless manager. Either there is a systematic list of tests to perform and equipment to test or it is a hit-and-miss operation.

    • (Score: 1, Funny) by Anonymous Coward on Wednesday July 10 2019, @09:16AM (3 children)

      by Anonymous Coward on Wednesday July 10 2019, @09:16AM (#865325)

      Extensive field test... that's where they got people to test it but didn't pay them, right?

      • (Score: 2) by Booga1 on Wednesday July 10 2019, @10:45AM (2 children)

        by Booga1 (6333) on Wednesday July 10 2019, @10:45AM (#865334)

        Extensive field test... that's where they got people to test it but didn't pay them, right?

        Yep. Tech sites and Youtube product reviewers that got units in advance and were told they couldn't talk about it until the official announcement.
        They probably found the issues and figured it was a quirky pre-release unit and just worked around it and didn't bother reporting the problem since getting reliable power over USB for a Raspberry Pi is already a "known issue."

        • (Score: 4, Insightful) by Knowledge Troll on Wednesday July 10 2019, @11:58AM

          by Knowledge Troll (5948) on Wednesday July 10 2019, @11:58AM (#865345) Homepage Journal

          They probably found the issues and figured it was a quirky pre-release unit and just worked around it and didn't bother reporting the problem since getting reliable power over USB for a Raspberry Pi is already a "known issue."

          I like that theory but I'm going to toss out another one: blame the user. Not just with RPI but with Odroid as well, both from the vendor and from the Armbian project, blame the user is standard course of action with a trouble report. This does not include listen to the user and it doesn't include understanding the user report. It is just blame the user. And I'm sure it developed because most users were wrong.

          But the problem is when you have a user that is right they are also blamed. I had an Odroid in a specific physical configuration with some devices on USB. I applied an Armbian OS update which included a kernel change, rebooted, and USB was dead. Went to get help and was told my power supply sucks ass. Well it's the vendor recommended power supply. It was some form of power issue, they were right about that because moving the USB off to a power hub solved the problem, but it worked fine before the kernel change and didn't work after.

          I have two models of Odroid units, one of them works with my TV via HDMI and one does not. For the one that does not work with HDMI there is a FAQ. In the FAQ is an entry that says if this thing doesn't work with your TV it's because your TV uses fake HDMI and there is just nothing that can be done about it so replace your TV with a good one. Thanks for insulting my TV. They might be right, I don't know how fake my HDMI implementation may be, but as for the idea that nothing can be done? The TV works fine with Armbian on the exact same device but not the Odroid supplied Ubuntu.

          As far as I can tell this bullshit permeates the entire Linux ecosystem of cheap well known ARM SBC. I've not yet had my Atomic Pis bite me and they are running unmodified Debian. It's the first things they aren't painful and actively fucking with me.

        • (Score: 2) by RS3 on Thursday July 11 2019, @04:11AM

          by RS3 (6367) on Thursday July 11 2019, @04:11AM (#865670)

          Yep. Tech sites and Youtube product reviewers...

          But will it blend?

    • (Score: 4, Interesting) by theluggage on Wednesday July 10 2019, @01:11PM (2 children)

      by theluggage (1797) on Wednesday July 10 2019, @01:11PM (#865361)

      I'd cut the Pi a bit of slack because there's no secret that its aggressively built down to a price - and good testing costs money. The major point of the Pi is that it is sufficiently cheap that you can tinker with it and not cry into your beer if you let the magic smoke out. Its not as if premium-priced products with high margins don't have design glitches...

      Its not good to have a fault, but mostly, people are going to power the Pi with the cheapest adapter they can find that can supply enough juice, which normally involves getting one that's been tested with, or specifically sold for, the Pi.

      The Pi is meant to evoke the spirit of the BBC Micro and Sinclair ZX computers... I think they've nailed it :-) (I had to drill extra ventilation holes in the top of my Issue 1 BBC Micro to stop the wires in the power supply melting... and wiring up a working serial cable for those beasties was a dark art...).

      • (Score: 2) by driverless on Wednesday July 10 2019, @11:35PM (1 child)

        by driverless (4770) on Wednesday July 10 2019, @11:35PM (#865559)

        The problem with the Pi is that there's an endless series of products build around it by people who don't realise it's a kid's toy. If it was marketed as an educational toy and stayed there I'd be fine with it, but now that there's dozens (hundreds?) of commercial products out there using this Trabi hardware, and no end in sight, it's become everyone's problem. Sort of like when "professional workstation" meant Windows 3.1.

        • (Score: 2) by RS3 on Thursday July 11 2019, @04:14AM

          by RS3 (6367) on Thursday July 11 2019, @04:14AM (#865671)

          The problem with the Pi Windows is that there's an endless series of products build around it by people who don't realise it's a kid's toy.

          FTFY.

    • (Score: 4, Insightful) by DannyB on Wednesday July 10 2019, @01:55PM

      by DannyB (5839) Subscriber Badge on Wednesday July 10 2019, @01:55PM (#865377) Journal

      It DID show up in their field testing program.

      Their field testing program consists of selling the devices to the public for testing porpoises.

      What? You didn't expect their field testing program to actually test fields before release did you?

      --
      The most difficult part of the art of fencing is digging the holes and carrying the fence posts.
  • (Score: 3, Informative) by takyon on Wednesday July 10 2019, @06:00PM (3 children)

    by takyon (881) <reversethis-{gro ... s} {ta} {noykat}> on Wednesday July 10 2019, @06:00PM (#865445) Journal

    Wait until they put out a fixed up 8 GB version:

    https://hackaday.com/2019/06/25/is-4gb-the-limit-for-the-raspberry-pi-4/ [hackaday.com]

    We can look forward to an 8 GB Pi 4 then at some point in the future. We’d put our money on next year, since 2020 is a leap year and 2020-02-29 will be the Pi’s 8th birthday, it wouldn’t stretch the imagination to speculate around that date. But don’t bet on it, save your money for buying a 4 GB Pi 4 right now.

    --
    [SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
    • (Score: 2) by DannyB on Wednesday July 10 2019, @06:58PM (2 children)

      by DannyB (5839) Subscriber Badge on Wednesday July 10 2019, @06:58PM (#865464) Journal

      If I'm going to save my money to buy a 4 GB Pi 4 right now, I wonder how long I should set up that savings plan for? Once I save up the required amount, will the Raspberry Pi foundation have come out with a revised board that corrects the USB C port problems?

      --
      The most difficult part of the art of fencing is digging the holes and carrying the fence posts.
      • (Score: 2) by takyon on Wednesday July 10 2019, @07:44PM (1 child)

        by takyon (881) <reversethis-{gro ... s} {ta} {noykat}> on Wednesday July 10 2019, @07:44PM (#865478) Journal

        IDK. Does "future board revision" mean they can push out the change to all newly manufactured units without introducing a new model? If so, it could happen sooner. But the word "future" there does not bode well for how much they care about this.

        --
        [SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
        • (Score: 2) by driverless on Wednesday July 10 2019, @11:38PM

          by driverless (4770) on Wednesday July 10 2019, @11:38PM (#865561)

          Given that they managed to make the 3B+ incompatible with the 3B (two variants in the same product series, not even a new version), I'm pretty sure "future version" will mean "incompatible version".

  • (Score: 2) by linkdude64 on Thursday July 11 2019, @02:23AM

    by linkdude64 (5482) on Thursday July 11 2019, @02:23AM (#865626)

    They never intended or wanted it to be a compliant USB C port - they want it to work only with their chargers, and only output display on their bases. This is not just good business financially, it's good business from a user experience standpoint. Generally, most Nintendo peripherals are extremely high-quality and well tested.

  • (Score: 2) by darkfeline on Thursday July 11 2019, @03:12AM

    by darkfeline (1030) on Thursday July 11 2019, @03:12AM (#865649) Homepage

    This is the hardware equivalent of "What happens when I comment out this if block? Don't think we need it." Whoever decided to take a clever shortcut around the spec should have double checked with a(nother) electrical engineer.

    --
    Join the SDF Public Access UNIX System today!
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