You need to add a new screen with

Code:
MCFG_SCREEN_ADD("screen name", RASTER) ...


For the VSYNC there is a callback you can add:

Code:
MCFG_UPD7220_VSYNC_CALLBACK


EDIT: MCFG_VIDEO_SET_SCREEN needs to be added after your 7720 device in the machine config, not after the screen.

Last edited by Duke; 08/15/16 10:09 AM.