This is exactly what I learned for the first Hewlett Packard mainframe machines ksorry model number gone from memory). I first keyed in the "basic binary loader" using the toggle switches.  That woke up the pinched tape reader then fed in a couple of feet of tape.  Maybe that was the BBL, then the program tape I punched out on the M33.  Long process.  This was all -hp- basic.  I had to learn all this stuff on my own, never got comfortable although I earned to write elementary programs.  I think the combinations keyed in with the toggle switch were called the basic binary bootstrap.  For years I had that memorized and carried the BBL tape folded up in my wallet.