Need help trying to play a FDS game on Nestopia

I trying to play fds file with FCEUX using this bios
but when I click on play game then didn't nothing happens but only see popup message
like that: please insert cartridge on B side

Please help me how I fix this :(

If it says to insert side B, then assuming that you're using Nestopia, just hold down the shift key and press B, that changes the side of the disc, it will take a few seconds to load after that.

@Glitchy

Use Nestopia, it is by far the best lightest and quite accurate NES emulator.

Leagues better than FCEUX.

to switch sides you can do what rmcin329 said or use the GUI tabs to make the switch.

Thanx all buddies for your help

I find answer at my problem

That was occured becouse I'm not click it few button's on fceux
and for now I smilling just yourself for that

ahhahha :P