Thanks. Nice links. I love the handwritten assembler pic with mapping from mnemonics to op codes. If you had to punch it in on a hex keypad, you absolutely needed that. Unfortunately, I never was organized enough to have different color pens :-)

As a high school student I didn’t have the money to buy a 6502 assembler and I used to write my assembly code out in long hand on graph paper, hand-assemble it and type in the hex in the monitor.