Ah, the "joy" of loading the assembler from the the cassette tape recorder from one tape, then switching the tape to load the code I work with, then changing it and then saving it on the tape before the run it since it will be lost if it crashes or just enters the loop. Then I've added the NMI hardware which allowed me to break the loop and keep the upper piece of the memory. And like some commenters also mention, that computer also didn't have the "real" keys.

But don't get me started on using the switches to input the single bits over the console on the even older computer.