Connecting moteino

[Naarlack]

I ordered it earlier this year so I don't think so. It says R2 on it.

Photo is attached.

[Felix]

Yes this is the latest version as of now. Please try another computer and let's see the results. People had bad USB ports, bad cables, bad drivers. Lots of things can be at fault. Even the adapter itself. But they are all tested on a known good computer before they are sent out. So between here and there something happened, or maybe not (likely not but possibly). Let's try finding the problem by elimination.

[Naarlack]

It works on my old laptop fine.

But only works when I use it through a USB hub on my main PC. It is not a problem really; I'll just use the hub. But I was curious why it works with the hub but not when I plug in directly to the USB port on the front of the computer.

[Felix]

Probably something faulty in that USB on the front of your computer?
I see this again and again.

[TomWS]

It works on my old laptop fine.

But only works when I use it through a USB hub on my main PC. It is not a problem really; I'll just use the hub. But I was curious why it works with the hub but not when I plug in directly to the USB port on the front of the computer.

That it works on a powered Hub and a laptop seems to indicate that the device is consuming more that 100mA at the time of enumeration.  The USB spec says that ports don't need to supply more that 100mA to any port until the device enumerates as tells the OS how much power it needs.  PCs generally adhere to this spec, Laptops don't always as they tend to have features like using USB ports as device charging ports, and powered hubs simply supply full power because its cheaper to do it that way...

Tom

[Felix]

Thanks Tom for the explanation.
I see a difference here though. MoteinoUSB works fine (essentially FTDI+Moteino in 1 board). FTDI + regular Moteino does not work.
I wonder if the FTDI alone enumerates and the problem is only at upload time? That could explain the issues with these PC USB ports.

[TomWS]

Thanks Tom for the explanation.
I see a difference here though. MoteinoUSB works fine (essentially FTDI+Moteino in 1 board). FTDI + regular Moteino does not work.
I wonder if the FTDI alone enumerates and the problem is only at upload time? That could explain the issues with these PC USB ports.

The key is whether the FTDI chip disables power to the device until enumeration is complete (assuming that the combined power is greater than 100mA).  With a Moteino, the power consumption on power up could be > 100mA if the radio is in some powered on state, seems unlikely, but still...   What may be more likely is that the combined capacitance of the device is such that there is a >100mA surge when it's first plugged into the port.  This could cause the enumeration to fail, it also tends to cause rather random effects depending on which system it's plugged into.  DAMHIKT!   

With the Moteino it's relatively easy to solve - plug the cable into the computer BEFORE connecting to the Moteino.  The FTDI dongle enumerates properly and then the Moteino can be powered from the cable.  The Moteino USB doesn't allow this approach.


Tom