I have been asked a few times if there is a way to convert a basic USB cable to allow it to connect to your WGR614L/WNR3500L.

The answer is basically no - allow me to explain.

First of all I recommend the USB-to-Serial Cable: 3.3V TTL cables that are available here. They come with different types of connectors Bare Wire, 6 Pin SIP and Audio Plug Connector.

But the business end, the USB side is very different than a standard USB cable.

The key to these cables are that each one contains a small internal electronic circuit board, utilizing the FT232R chip, which is encapsulated into the USB connector end of the cable. They use FTDIÂ’s FT232RQ USB to Serial UART interface IC device which handles all the USB signalling and protocols.

These cables require USB drivers to make them work, but they are available free from http://www.ftdichip.com which is then used to make the FT232R chip in the cable appear as a virtual COM port (VCP) on your computer. This allows you to communicate with the USB interface via a standard PC serial emulation port (for example TTY or PUTTY).

You could buy a Mini-USB to Serial UART (TTL) Breakout Board, 3.3V and plug a standard USB cable into it and then solder wires from there but for a $5.00 savings it's probably not worth it.

They also make other boards or you can just buy the chip by itself; at the end of the day, I just don't think it is worth the effort compared to buying the cable itself.

If you like hacking like I do and may brick your router a few times while playing with it get the right cable and make it easy to debrick as shown here for the WGR614L and here for the WNR3500L.