I remember that. For whatever reason 3d0g would get me out of it. I was just a kid and had no idea what to do with the gibberish that the assembler would spit out at me. I just knew how to get out and back to my prompt.
CALL -151: Think "65536-151" - jump to $FF69, which was the monitor ROM entry point.
3D0G: 0x3D0, "Go": Run the code that DOS put at location $03D0. I believe it was a 4C BF 9D, as in, JMP $9DBF, which was the DOS 3.3 entry point/warm start routine.
Damn, I'm old. After a long and convoluted ride through the IT world, I got to retire early because I spent my early teenage years messing around with that sort of thing. It was pure luck that I got my hands on the right machine at the right time, developed a love of computing at a time when home computers were regarded as nothing more than means to store recipes (mom), do taxes (dad), or play games (kids).
Anyways. Thanks, Apple guyz, for putting a disassembler into ROM. It's only been in the past few years that I realized just how much of an impact that comparatively minor technical decision had on my life.