Hi,
Actually I never know what is Motorolla 2nd Gen before. But I'm Familiar with SRF ultrasonic family and I2C Communication protocol. Because I have became Embedded engineer and using various kind of I2C based IC since 2012. The global concept is same, what is different is the architechture between vendor, So, I think I could do this project for about 2-3 day. Just need to adopt to your system. I have used I2C for STM32,AVR,Arduino, and many other microcontroller and FPGA. So, Lets discuss the detail over chat.
Best Regards,
Rijal