PS4100X firmware download

Hello,

Is there a link for the latest firmware for the Equallogic PS4100X available?  We got a new controller and now the firmware versions are mismatched.  

Active Controller is version V6.06 (R351932)

Secondary Controller is version V8.1.1 (R417753).

We can either move the active to the same level as secondary or move them both to a higher version.  I'm fine with either.  We are using this in a VMWare vCenter Server 6.0.0 build 7924804.

James