I am a starter, with Arduino UNO R4 (not cloned) and IDE 2.3.7 on my Mac book pro. I have tried several USBC to USBC cables and non of then works, including an USB-C 2.0 3ft USB C to C Cable Supports up to 480Mbps data transfer speed for syncing and charging. The problem is that the cable does not power the UNO board. I cut one the of the cables open and found that there is only one C lines. I added a pull down resistor to this line and it then can power the cable, but the upload is very unreliable, only worked occasionally with all the resetting the UNO, plug/unplug, and the problem is not related with IDE. On the bash terminal, ls: /dev/cu.usbmodem*: show no such file or directory in most of the cases. The board only works when ls: /dev/cu.usbmodem* shows /dev/cu.usbmodem101.
Now I am not sure if this is the cable problem, Mac problem or the UNO R4 problem. Could any one suggest a good USBC cable that is known for sure to work between MAC and UNO R4 board?
I looked at several Amazon USBC data cables and found there are missing pins in the port.
Also Apparently, the UNO R4 does not have a pull down resister for the C lines. Anyone have a solution? please......
Can you try to connect a USB 2 hub and connect your arduino to the hub - if you have one?
Order some from Apple and mark them as good. Many places sell USB charge-only cables, as the vast majority of people need only that. I have owned several Macs and have encountered a few data-only or charge-only cables. I bought a USB cable tester (2 actually) and if I am having trouble testing the cable.
Did you mean that the USB C slot is USB 3, too fast for the Arduino?
Thanks but Apple cables are mostly for charging. I have tried one and it didn't work. could you please suggest a particular one I should buy?
If you read the description you will see that is not true.
and is ideal for charging, syncing, and transferring data between USB-C devices.
I use this one with an M2 Mac.
No - more that some Macs, especially newer ones with USB-C and Apple Silicon have strict power delivery behavior and will try to protect the Mac and its USB port if things don't seem right. Some Arduino boards, especially clones, can have weak or poorly designed voltage regulation and USB circuitry. A good hub (esp USB 2 as it uses only the USB 2 wires) will present a stable device to the Mac, and is usually more lenient and can absorb the differences, smoothing out voltage dips or spikes.
The Uno R4 states in the user manual that the USB C cable shouldn't provide more than 5V which I think means the Uno R4 doesn't support PD.
Support PD just means presence of the resistors hooked up to the correct pins and it will then be delivered 5V, is that right?
I think if the resistors are missing the default is 5V. They are shown to be 5.1k on the R4 Minima schematic so it should be asking for 5V.
I'm not sure about the 5V only comment in the user manual now.
100% NOT true. I have ordered several in the last couple weeks, one short Thunderbolt 4 (USB-C) for my Time Machine SSD, a longer Thunderbolt 4 (USB-C) for general 40GBps data transfer AND a charge only.
I don't think so, it's more complicated, but in any case a USB-C cable has dedicated 5V pins for backward compatibility. PD conections use electronic boards located in the ends of the cables.
Apple itself does not sell any cables that are strictly charge-only. All Apple-branded USB-C or Lightning cables support both charging and data transfer.
This is exactly where I am confused of. My first USB C- USBC cable is a "data cable", but did not provide power ( light on the board). I cut the cable open and found there is one C line. I added a 5.1K pull down to this line, and the cable works, the board lights up, can upload a few simple programs, but it soon broken, will power ok but on he Mac the bash terminal ls /dev/cu.usb* command could not reliably find a USB port.
I then purchased another USBC to USBC data cable, but it failed to provide power on the UNO R4 minima. According to the circuit diagram (ABX00080), there are two pulldown resistors on both C1 and C2. So why a USBC data cable didn't provide 5V?
The bottom lines:
- Any charging cable can provide 5V to the board, but can't upload. program already uploaded runs ok on charging cable power.
- I have tried 2-3 USBC "data" cables but none can provide power.
- the data cable I have hacked with a 5.1k pulldown resistor works occasionally , not related to the IDE ( Bash terminal can occasionally recognize the UNO board).
Thank you all for the discussion. This is a really confusion problem.
Yes. but it didn't work on my UNO Minima. Mine is not a clone, real R4 assembled in Italy, two 5.1Ks are shown in the schematic diagram. Now charging cable can provide power but data cable can't.
thanks will order the short TB4.
I use that USB A to Lightning cable to both charge and sync with an Apple device.
I also have a Mac and an Arduino UNO R4. The first and every time since I plug it in with a common USB-C cable it works fine. No need to add resistors, do you really think their engineers are so careless?
Do you have a USB cable tester?
This is the any to any tester on Amazon.ca change the country as needed LINK
Here are some pics of my testers and different cables
This is the Thundedrbolt 4 (USB-C) data rate of 40GB/sec. it is plugged into an SSD so also supplies power.
This is the USB-A to Apple Lightning. ONLY power as you can see (VBUS and G) on the right side
I also have a Mac and an Arduino UNO R4. The first and every time since I plug it in with a common USB-C cable it works fine. No need to add resistors, do you really think their engineers are so careless?
Do you have a USB cable tester?
Here is one on Amazon.ca, change country as required LINK
I also haver another one that is USB only, and is just a continuity checker. The interesting part and proof of embedded electronics is that it looks like not all wires are connected at each end. If you then turn the connector on the right upside down the lights are the same, BUT if you flip the left over the lights change sides, the side with the most lights will change from A to B.
