Need documentation for a really old 9 DOF Razor


I have a really old 9DOF Razor that is serial output only. It is currently set at 57600 baud and I would like to slow it down. Does Sparkfun or anyone else have the documentation for this particular 9DOF?
Thanks,
David

This appears to be for the ATmega328P version: GitHub - Razor-AHRS/razor-9dof-ahrs: AHRS Firmware for the SparkFun 9DOF Razor IMU and SparkFun 9DOF Sensor Stick