8 bit glory

Atari systems

• 64 kB RAM
• 24 kB ROM
  • 16 kB for OS
  • 8 kB for BASIC or cartridge
• Processor
  • MOS 6502
• Text mode
  • 40x24 monochrome
• Graphics modes
  • 320x192 monochrome
  • 160x192 4 colors
  • 80x192 16 colors
• Sound
  • PSG
• Cassette recorder
• Floppy disk support
  • cost!
• SIO
  • serial input/output
  • the same author created USB years after!

MOS 6502

• 8 bit CPU
• 16 bit address bus (64 kB)
• 1975
• 1.6 MHz
• no multiplier nor divider
• one GP register: an accumulator A
• two index registers: X and Y
• 56 instructions

Programming Atari

• Atari BASIC
• Other BASICs
  • Turbo BASIC XL
  • Microsoft Basic (ugh!!!)
• Assemblers
  • Atari Assembler Editor
  • Atari Macro Assembler (ATASM)
  • SynAssembler
• Some compilers
  • Pascal

Atari BASIC

• implemented in 8kB ROM
• circa 37kB available RAM (- video RAM)
• so-called full-screen editor with line numbering
• support for graphics and sound
• tokenization on the fly
• built-in functions with one parameter (every)
• many statements and few control structures
• error checks on the fly
• line numbers
• global variables only (127)
• no user-defined functions
• two primitive data types: number, string
• string arrays, number arrays and matrices
• FOR-loop and GOTO everywhere :)
• computed GOTO
• TRAP for error catching

Live demo

SynAssembler

• implemented in 8kB ROM cartridge
• editor/assembler/monitor
• controlled by CLI commands
• no help, no menu, almost no error checks

Live demo