Two weeks ago, the Raspberry Pi Foundation announced the Raspberry Pi 4. It’s a future-proof computer with two Micro HDMI ports, up to 4GB of RAM, and a poorly designed USB-C port that won’t work with some USB-C cables.
The Pi 4 Isn’t USB-C Compliant
USB-C is a universal format. The reason people are so hyped on USB-C is that, unlike other charging cables, it just works. But when a device with a USB-C port isn’t USB-C compliant, it will always run into unexpected problems.
And, as you’ve probably guessed by now, The Raspberry Pi Foundation didn’t follow the official USB-C guidelines. As reported by Tyler Ward (Scorpia), the Pi 4’s circuit board uses a single 5.1 K ohms resistor for two separate CC pins. This violates the official USB-C guidelines, which mandate that each CC pin is supposed to have its own resistor.
In layman’s terms, the Pi 4 isn’t USB-C compliant. And, as of right now, its noncompliance has only caused one problem: incompatibility with certain USB-C chargers/cables.
The Pi 4 Doesn’t Work with E-Marked Cables
E-marked cables are “smart” USB-C cables usually packaged with expensive devices, like the MacBook Pro. They’re capable of detecting the device they’re plugged into, entering USB-C alt modes, and regulating power.
E-marked cables are supposed to work with all USB-C devices, not just laptops and phones. But because of the Pi 4’s noncompliant design, e-marked cables recognize the Pi 4 as an audio accessory and refuse to put out a charge.
How do you know if a cable is e-marked? Well, you’ll have to check the packaging if you still have it. USB-C cables aren’t labeled as “e-marked” or “not e-marked.” Of course, you could just use the Pi 4 as an e-mark detector or buy a cable guaranteed to work with the Pi 4.
Use “Simple” Cables, Like The Official Pi 4 Cable
The Raspberry Pi Foundation claims that it will fix its USB-C problem in the next revision. But if you’ve already pre-ordered a Pi 4, congratulations! You can’t use e-marked cables with your device. So, what now?
Technically, you can use any “simple” USB-C cable with the Pi 4. That leaves you a lot of options, but we’d recommend sticking with the official Pi 4 cable. The Raspberry Pi Foundation clearly didn’t test a variety of cables with its charging port (otherwise it would’ve known about this issue), so there’s a chance that even some “simple” USB-C cables will have trouble working with the Pi 4.
If you don’t want to pay $8 for the official Pi 4 cable (it’s kind of bulky, we understand), you can take your chances with a “simple” USB-C cable and a fast charging or native USB-C power brick. The Pi 4 needs 15.3 watts of power, and most cheap or outdated power bricks can’t push that kind of wattage. There’s still a chance this won’t work, of course, so your mileage may vary.
Sources: Scorpia, Benson Leung