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By jywmpg
#198686
Is it possible to hang a USB-to-Serial cable off the micro USB connector on the Fio V3?

Background
My Fio V3-based application controls a serial device remotely using an XBee. It uses Serial1 to talk to the XBee, and SoftwareSerial on pins 10 and 11 to talk to the serial device. That part works fine.

This leaves the micro SD connector essentially free, since the FIO can be powered separately via the 3V3 and GND pins.

The box with the FIO will be installed in close proximity to a wireless router that has a spare DB-9 connector, which can be mapped to a TCP port and accessed from the internet.

It would be really convenient to be able to connect the micro USB connector on the FIO with the spare DB-9 connector on the router to allow us to access the FIO's Serial port from the internet. This would give us redundant communication paths by which we can control the serial device, which is highly desirable for our application.

Apparent (Non) Solution
I found a device that has the right set of connectors, and would allow us to power the Fio via the USB connector as well, the StartTech ICUSBANDR232 https://www.startech.com/Cards-Adapters ... USBANDR232. However, it is made for the Android, and I have not been able to get data to flow down the serial cable using the Fio.

So, back to the main question: Is it possible to connect a USB-to-Serial cable to the micro USB port on the Fio V3?

Thanks,
jw
By Valen
#198697
The USB connector on the FIO needs to be connected to a USB host, like a computer. The FIO is a USB-slave and cannot act as a USB host. (Well, maybe with a serious rewrite of the firmware. But I haven't heard of any) You'd have to implement a second software serial port on different digital pins to connect with the router's serial port. But with 2 software serial port timing issues may arrise.
By jywmpg
#198707
Thanks again for taking the time to write. I appreciate it.

I pretty much came to the same conclusion over the weekend, but it is good to have someone else confirm it.

I'd need a USB host port to plug the slave USB-to-Serial converter into, and the Fio does not offer that. It offers a bunch of things, but not that particular one.

The extra port would have been icing on the cake for this application, but we can run fine without it. The Fio is a pretty neat little device.