Update README.md add RX-V681

README.md

@@ -5,7 +5,7 @@ Package to control Yamaha receivers that support the YNCA protocol.
 According to reports of users and info found on the internet the following receivers should work.
 There might be more receivers that support this protocol. If you find some let met know so the list can be updated.
 
-> HTR-4065, HTR-4071, HTR-6064, RX-A660, RX-A700, RX-A710, RX-A720, RX-A740, RX-A750, RX-A800, RX-A810, RX-A820, RX-A830, RX-A840, RX-A850, RX-A1000, RX-A1010, RX-A1020, RX-A1030, RX-A1040, RX-A2000, RX-A2010, RX-A2020, RX-A2070, RX-A3000, RX-A3010, RX-A3020, RX-A3030, RX-A3070, RX-S600D, RX-V473, RX-V475, RX-V477, RX-V481D, RX-V483, RX-V575, RX-V671, RX-V673, RX-V675, RX-V677, RX-V679, RX-V771, RX-V773, RX-V775, RX-V777, RX-V867, RX-V871, RX-V1067, RX-V1071, RX-V1085, RX-V2067, RX-V2071, RX-V3067, RX-V3071, TSR-700, TSR-7850
+> HTR-4065, HTR-4071, HTR-6064, RX-A660, RX-A700, RX-A710, RX-A720, RX-A740, RX-A750, RX-A800, RX-A810, RX-A820, RX-A830, RX-A840, RX-A850, RX-A1000, RX-A1010, RX-A1020, RX-A1030, RX-A1040, RX-A2000, RX-A2010, RX-A2020, RX-A2070, RX-A3000, RX-A3010, RX-A3020, RX-A3030, RX-A3070, RX-S600D, RX-V473, RX-V475, RX-V477, RX-V481D, RX-V483, RX-V575, RX-V671, RX-V673, RX-V675, RX-V677, RX-V679, RX-V681, RX-V771, RX-V773, RX-V775, RX-V777, RX-V867, RX-V871, RX-V1067, RX-V1071, RX-V1085, RX-V2067, RX-V2071, RX-V3067, RX-V3071, TSR-700, TSR-7850
 
 Note that only 1 YNCA connection to a receiver can be made at the time (restriction on the receiver side, not this library).
 Usually not a problem as the Yamaha AV Control App uses a different protocol which can be used at the same time, but something to be aware of when testing the library.