Prerequisite Knowledge#

Before the toolchain and your first ROM, a handful of fundamentals make everything that follows legible. None of them is really “programming” in the usual sense — they are the mental model the VCS forces on you, and the rest of the book quietly assumes all of them. The throughline: you must understand the display you’re driving, the notation the code is written in, and the way data is just bits at addresses.

Work through them in order, then head to Getting Started to set up your tools and build a ROM.

  • How a Television Works — the beam, scanlines, frames, sync, and NTSC vs. PAL. The display medium that dictates everything else.
  • Reading 6502 Assembly — mnemonics, operands, labels, and directives: just enough to follow the code in every later chapter.
  • Thinking in Bits — binary and hex, masks, and the four bit operations.
  • Numbers & Arithmetic — signed values via two’s complement, carrying between bytes, and life on a chip with no multiply.
  • The Memory-Mapped Interface — registers as addresses, write-only and strobe registers, and reading live hardware state.
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