🍓 ACORN ATOM

EMULATOR · 6502 · MC6847 · 8255
Awaiting ROMs…
ROM CARTRIDGE SLOTS
Upload any file, any extension. Bytes load raw into memory.
Atom BASIC ROM
→ $C000 (8 KB)
Drop Atom_Basic.rom or any file
Floating Point ROM
→ $A000 (4 KB)
Drop Atom_FloatingPoint.rom or any file
Kernel ROM (COS)
→ $F000 (4 KB)
Drop akernel.rom or any file
Warming up 40-year-old silicon… Need ROMs? Grab Atom BASIC, FP & COS images from Acorn archives — any extension works here.
MC6847 VIDEO DISPLAY
DISPLAY OFF
MEMORY MAP $0000–$FFFF
$F000 Kernel ROM (COS)
$E000 DOS ROM / Expansion
$C000 Atom BASIC ROM
$BC00 Paging control (#BFFF)
$B800 6522 VIA (Printer/Serial)
$B400 Extension I/O (PL8)
$B000 8255 PPI (Keyboard/Cassette)
$A000 Floating Point ROM
$9800 Empty / Reserved
$8000 On-board RAM Expansion
$4000 Commercial Expansion RAM
$2C00 Extension Graphics RAM
$2800 Graphics/Screen RAM
$0A00 Extension RAM
$0400 Lower Text Space (User RAM)
$0000 Zero Page / Stack / OS vars
Keyboard: type on your real keyboard — routed through the emulated 8255 PPI matrix at $B000. F12 = BREAK. Tab = REPEAT. Shift & Ctrl supported. On mobile, tap the on-screen keys.