Emulator Cheats

How can I make pcecd games cheat code for mess?
Is there any games of pcecd cheat for Mess for reference?
I have a plan to make invincibility code for faussete amour,I found address where flashing invincibility take place with build-in debugger ,but I failed to enable cheat options in config menu and it seems very complicated for myself.
It would very helpful if there is any guide for making a new cheat code for pcecd.
Thanks in advance.

I haven't got any pcecd games, but if it's anything like PCE then you need to make sure you are poking the correct memory region - which for RAM cheats on the PCE is 'r' .

For instance in the PCE softwarelist game 'advislnd' you need to enter this for infinite energy:-

maincpu.rb@1F141A=80