Writing G-code: Audible Alert at end of print
Let's put the parts one by one:


Wait for bed temperature being at 30 °C: M190 R30
Play Bleep for 1/5th of a second: M300 S440 P200
Wait for 1/5th of a second: G4 P200


That gives:

M190 R30
M140 S0
M300 S440 P200
G4 P200
M300 S440 P200
G4 P200
M300 S440 P200
G4 P200
M300 S440 P200
G4 P200


Just for 0scar:

M300 S1396.91 P400 ;f7
G4 P400
M300 S1661.22 P600 ;as7
M300 S1396.91 P400 ;f7
M300 S1396.91 P200 ;f7
M300 S1864.66 P400 ;b7
M300 S1244.51 P400 ;es7
M300 S1396.91 P400 ;f7
G4 P400
M300 S2093.00 P400 ;c8
M300 S1396.91 P400 ;f7
M300 S1396.91 P200 ;f7
M300 S2217.46 P400 ;des8
M300 S2093.00 P400 ;c8
M300 S1661.22 P400 ;as7
M300 S1396.91 P400 ;f7
M300 S2093.00 P400 ;c8
M300 S2793.83 P400 ;f8
M300 S1244.51 P400 ;es7
M300 S1244.51 P200 ;es7
M300 S1046.50 P400 ;c7
M300 S1567.98 P400 ;g7
M300 S1396.91 P1600 ;f7