Here's a lua cheat that works with the change just pushed for zelda that sets the clock. Put it in "cheat/gnw_zelda.json" and run mame with "-plugin cheat" and look in Plugin Options/Cheats.
Code
[{
"desc": "Set clock to current time",
"space": {
"cpu": {
"tag": ":maincpu",
"type": "data"
}
},
"script": {
"on": "local lt = os.date('*t') cpu:write_u8(16, lt.min % 10) cpu:write_u8(17, lt.min // 10) local hour = (lt.hour > 12) and (lt.hour - 12) or lt.hour if lt.hour == 0 then hour = 12 end cpu:write_u8(18, hour % 10) cpu:write_u8(19, (hour // 10) + (((lt.hour > 12) or (lt.hour == 0)) and 10 or 0))"
}
}]
