Xemu won’t even blink without it.
If configured correctly, you should see the classic green flubber animation, signaling that the MCPX ROM has successfully handed off control to the BIOS. A Note on Versions: 1.0 vs. 1.1 You might occasionally see references to mcpx-1.1.bin . xemu mcpx-1.0.bin
Once you have legally obtained your mcpx-1.0.bin (usually 32,768 bytes exactly), you need to tell xemu where to find it. The xemu interface has changed over the years, but the logic remains. Xemu won’t even blink without it