Incorrect CC pins configuration - doesn't work with USB-C to USB-C cables

[bramstroker]

Hi @AlexCPU, thanks for your project — it was exactly what I needed for my MOC build.

I ordered the assembled board from xelaser and received it last week. I finally got around to installing it today, but I'm running into issues connecting the device via USB to flash the firmware.

I first tried on my MacBook Pro, and installed the CH340 driver. However, no new USB devices show up when I check with ls /dev/cu.*, and ESPHome Web also doesn't detect the device. I tried three different cables and all USB ports, and also held the BOOT button while connecting, but still no luck.

Next, I tried a Windows 10 PC, but I don’t hear any USB connection sound when plugging in the board. Even without drivers, I’d expect at least a connection tone.

At this point, I’m suspecting the board might be faulty, but I’m not entirely sure. Any advice on what else I could try?

[AlexCPU]

Hi @bramstroker,

I did have some issues with USB cables on this latest batch that sound similar to what you are describing, I just found another cable which worked and assumed I had a dodgy cable. However...

Having now investigated further, it looks like you've found a bug in the hardware design that you're probably more disposed to by only having USB-C ports on the MacBook Pro.

R1 and R2 should be pull-down resistors rather than pull-up resistors. In their current configuration, they are set up to tell the USB-C interface that they are the "host" device, which is why your computer can't see anything, as both ends of the link are claiming to be the host.

I've confirmed this with some USB-C cables, laptops and charger/power-supplies.

If you use a USB-A to USB-C cable, it should power up fine. And also work with an A-C adapter on the end of that cable (the A end has to be in the laptop not the PCB, as it defines the host end of the cable itself).

One final point, you shouldn't need to program it, they were all programmed and tested before shipping. Once powered up with an A-C cable, it should put up a Wi-Fi access point for you to connect to and give your network details to.

[bramstroker]

Thanks for your answer and clarification.

I completely missed the firmware was pre-installed. Just connected the board using a USB charger with A-C cable, and was able to connect to the provided ap. Set up my own WiFi and up and running.
Now I can take control in HA and upload modified firmware using OTA.

Thanks a lot!