Transit Card Research

Research date: 2026-05-09. These notes capture public implementation checks and CoreExtendedNFC decisions behind transit-card balance work.

Japan IC

• FeliCa system code: 0003.
• Balance service: 008B, encoded for CoreNFC as 8B 00.
• Balance bytes: block bytes 11-12, little-endian, JPY.

Hong Kong Octopus

• FeliCa system code: 8008.
• Balance service: 0117, encoded as 17 01.
• Formula in HKD cents: (raw - 350) * 10.

China T-Union

• AID: A000000632010105.
• Primary purse APDU: 80 5C 00 02.
• Negative purse APDU: 80 5C 01 02.
• Final balance: primary purse minus negative purse, CNY fen.

KS X 6924

CoreExtendedNFC probes Hyundai, T-Money, Cashbee, EB Card, Snapper / MOIBA, and K-Cash AIDs and uses balance APDU 90 4C 00 00.