How many started coding for a machine writing machine code? I recall that the IBM 1620 SPS coding forms had two sides--one for coding assembly (SPS); the other labeled "IBM 1620 Absolute Coding System". Basically a form with the first 5 positions reserved for the address, 2 positions for the opcode and 5 positions each for the P and Q addresses.
You could enter the code from the form right into the console typewriter or punch it on a keypunch. If you were a real hard-case, you didn't bother with coding forms, you sat down at the typewriter and did everything from memory, mentally keeping track of storage addresses and what referenced them. Do this for a while and disassembly is easy. After all, you'll have all of the instructions and their opcodes committed to memory. I believe that I can still do this for 8080 code, in spite of my deteriorating wetware. --Chuck
