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Just tryin to understand

Nintendo age tutorials

1. Core programming concepts:
Instructions - smallest command run, one after another, NES has 56
Variables - place to store modifiable data
Control flow - instead of sequential, code can jump around

2. NES System Architecture
KB - Memory size is listed in KiloBytes or KB. 1KB = 1024 bytes. Everything is powers of 2, so 2^10 = 1024 is used instead of 1000. If the capitalization is different, the meaning can change. Kb is Kilobits. Divide Kb by 8 to get KB, because 1 byte = 8 bits.

ROM - Read Only Memory, holds data that cannot be changed. This is where the game code or graphics is stored on the cart.

RAM - Random Access Memory, holds data that can be read and written. When power is removed, the chip is erased. A battery can be used to keep power and data valid.

PRG - Program memory, the code for the game

CHR - Character memory, the data for graphics

CPU - Central Processing Unit, the main processor chip

PPU - Picture Processing Unit, the graphics chip

APU - Audio Processing Unit, the sound chip inside the CPU

3. Code layout

6502 references pages:

journal/spring2019/jwilli57/intro.1550154347.txt.gz · Last modified: 2019/02/14 09:25 by jwilli57