USB 2.0 to 2.5mm jack plug - cable or help needed

Hi Guys,
I do hope that you are able to help me with a problem I have.

I have a MF17 MiniRobot with an MR-C3024FX Rev 1.3 MCU. Called him Ted.

I need to build the USB 2.0 to 2.5 mini jack plug that connects a W7 PC to the MCU in the bot. and I cannot decide which of the two data wires from the USB plug needs to connect to the tip and/or ring of the jack plug . The USB has Black = G, Red = power, White = RX and Green = TX when I use it to connect a RPi to my PC. I assume that I need the Black to the Sleeve, I do NOT use/need the RED power lead and then I have the White or Green to the Tip or the Ring respectively.

I am loathe to just try it till it works coz if I clear the current program from the MCU or blow up the MCU I will have a dead robot
Or maybe someone has the cable in question and can sell it to me?
Best regards, Keep safe, ianm