Based on MAME 0.262 as of February 18th (after mamedev@76a99cb)
For GroovyMiSTer users:
- Download the correct package (Windows or Linux) and unzip it.
- Download
mame_mister.ini, rename it asmame.ini, and replace the default one in GroovyMAME's folder. - Edit mame.ini with your ip address (
mister_ipoption).