id: '574c4d191bfc',
  uuid: '574c4d191bfc',
  address: '57:4c:4d:19:1b:fc',
  addressType: 'public',
  connectable: true,
  advertisement: {
    localName: 'R1 Pro',
    txPowerLevel: undefined,
    manufacturerData: <Buffer 60 00 57 4c 4d 19 1b fc>,
    serviceData: [],
    serviceUuids: [ 'fe00' ],
    solicitationServiceUuids: [],
    serviceSolicitationUuids: []
  },
  rssi: -73,
  services: null,
  state: 'disconnected'


found service: fe00
found characteristic: fe01
found characteristic: fe02

in python code:
cmd = bytearray([247, 162, 4, 1, 0xff, 253])

original
bytearray(b'\xf7\xa2\x04\x01\xff\xfd')

after crc
bytearray(b'\xf7\xa2\x04\x01\xa7\xfd')