Normal ack is 0x11

- Fw 1.5, Packet 1, replaced first byte: 4a->3a
  ack = 22
- Fw 1.5, Packet 1, replaced two bytes: 4a->0a, 84 -> c4
  ack = 22
- Fw 1.5, Packet 1 replaced with packet 1 from fw 1.2a
  ack = 33, first packet ok
- Fw 1.5, Inserted packet 1 from fw 1.2a before original packet 1
  ack = 33, first packet ok
- Fw 1.5, Duplicated packet 1
  ack = 33, first packet ok