EDIT: As I was writing this I was able to resolve my issue, but will leave the solution here for others just in case. I've also made a couple recommendations for DFRobot's attention.

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Hi,

I've purchased 5x TEL0149 Gravity: BLE Sensor Beacon and 1 x 6-in-1 USB to Serial Converter (https://www.dfrobot.com/product-2291.html).

I have NanoBeacon config tool working as well, and have previously used it to program Sparkfun devices.

The issue is that when I attempt to connect to the Beacon, I get “failed to connect to the device” error.

I've tried the following:
1. Change out wires (twice).
2. Use a different beacon.
3. Check for beacon power (it gets 3v).

4. Installed drivers direct from SiliconLabs.

SOLVED: I had the Rx and Tx pins switched. Rx should go to Tx and Tx to Rx.

RECOMMENDATIONS:

1. By default, the 6-in-1 Serial Converter arrives misconfigured, so I had to configure the switches as shown on the product page (first configuration listed). It would be helpful to add this information to the product wiki, as I'm sure many people will run into the same issue.

2. The wiring diagram on the wiki is a bit small and blurry - it should be larger and also explicitly state that Tx should go to Rx. I know it's a noob mistake, but there are lots of noobs like me out there :).