Buffer = 37 bytes

Fixed : preamble 1B, sequence 1B, 33B payload, CRC16 2B

Host to machine : payload: command 1B, command specific

Machine to host :
0: preamble u8
1: sequence u8
2: status u16 (bitfield)
4: space size u16
6: free space u16
8: pos x i16 (steps)
A: pos y i16 (steps)
C: Npoint u16

Status
	15:12 protocol = 0
	4     button
	3     moving
	2     waitingNeedle
	1     running
	0     alive



