Some early machines were programmed by directly entering binary code. A number of switches to set location in RAM, more switches to set value that goes there, then push button / toggle a switch to write.
Same for machine functions: enable/disable certain features, write-protect some RAM areas, etc. Think old PC's turbo button, multiplied.
Same for machine functions: enable/disable certain features, write-protect some RAM areas, etc. Think old PC's turbo button, multiplied.