The Pennsylvania Supreme Court has upheld the Gaming Control Board’s decision to allow a casino at the Valley Forge Convention Center in King of Prussia. The court ruled Tuesday that it fits the definition of an Established Resort Hotel under the state law that legalized casino gambling. Greenwood Gaming and Entertainment, parent company of the Parx Casino in Bucks County, had appealed the Gaming Board’s decision. Parx, in Bensalem, is less than 25 miles away. The State Supreme Court ruling means the Valley Forge Convention Center owners can meet soon with the Gaming Control Board and discuss development plans. The casino’s license allows up to 600 slot machines and 50 table games, such as poker, blackjack and craps, for hotel guests and patrons of restaurants and other on-site facilities.