thanks to Fredrik Andersson (youtube) for reverse-engineering and sharing
NEJE Laser engraver protocol
baud 57600 8 data bits 1 stop bit parity none
0xf9 = stop/reset
0xf1 = start (Once issued incoming data will specify the position, data uses a modulus format.)
0xf2 = pause
0xf4 = engraving preview (visualizes bounding box)
0xf5 = go up
0xf6 = go down
0xf7 = go left
0xf8 = go right
0xf3 = go to left corner
<time in hex default= 0x3c (60ms)> burn time
0xfa = set motor parameter <hex speed default = 0x23 (35ms)>
0xfb = go to center
0xfc = fast backward <parameter 0x55> fast forward <parameter 0xaa> recarve <parameter 0x77> // Useful???
0xfe x8 = erase + send picture