For those interested, here is the implementation of enter for JPC emulator:
https://github.com/ianopolous/JPC/blob/master/src/org/jpc/em...
https://github.com/ianopolous/JPC/blob/master/src/org/jpc/em...
https://github.com/ianopolous/JPC/blob/master/src/org/jpc/em...
https://github.com/ianopolous/JPC/blob/master/src/org/jpc/em...
"JPC is a fast modern x86 PC emulator capable of booting Windows up to Windows 95 (and windows 98 in safe mode) and some graphical linuxes. It has a full featured graphical debugger with time travel mode along with standard features like break and watch points."