See Avoid the Noid HEX-code here!

For cheats in this game, use the DOS utility DEBUG. First backup your
game, then type the following from the DOS prompt:
                                        
For Normal game, type:
ren noid.exe cheater.cht
debug cheater.cht
For infinite lives, type:
e 1cd7 90 90 90 90
For stop time, type:
e 77cc 90 90 90 90
Then type:
w
q

For CGA game, type:
ren noid.exe cheater.cht
debug cheater.cht
For infinite lives, type:
e 1cd7 90 90 90 90
Then type:
w
q

Then rename CHEATER.CHT back to its previous name.