The V5 XL200 Hardware has an ARM processor as a replacement for the DSP processor.

The majority of the differences in the sofware(initially) are being isolated to the interface between the 80386EX processor and the coprocessor(DSP or ARM) and the coprocessor software itself.

The V4 hardware test software needed some minor changes to the DSP communication to use the Macros that hide the interface differences between the the DSP and ARM processors. This was done to test that the V4 hardware test still communicated correctly with the DSP before creating the V5 hardware test that will communicate with the ARM processor.