6502-VCSBIOS

BIOS ROM for the "VCS" computer in the A.C. Wright 6502 project.

Prerequisites

Install cc65 Toolchain

The cc65 toolchain provides the assembler and linker needed to build 6502 assembly code.

macOS (using Homebrew):

brew install cc65

Linux (Debian/Ubuntu):

sudo apt-get install cc65

Other platforms: See cc65 documentation

Optional: Install minipro (for EEPROM burning)

Only required if you plan to program an AT28C256 EEPROM chip:

brew install minipro

Building

Build the ROM image:

make

This generates:

• BIOS.bin - 32KB ROM image ($8000-$FFFF)
• BIOS.lst - Assembly listing file for debugging

Verification

View the generated binary as hex dump:

make view

Programming EEPROM

To burn the ROM to an AT28C256 EEPROM chip using a TL866 programmer:

make eeprom

Note: This requires a TL866 (or compatible) programmer and the minipro software.

Cleaning Build Artifacts

Remove generated files:

make clean