Z80 Assembly 52: Building a Simple OS - The Boot Sequence
The Kernel’s Entry Point Every Z80 system, upon power-on or reset, immediately begins executing the instruction at a fixed, low memory address. This is the boot sequence start, and it usually resides in Read-Only Memory (ROM). Common Reset Vector: The Z80 automatically jumps to address 0000H (the Reset Vector). The instruction at this address must be a jump to the main ROM code. Phase 1: Minimal Hardware Initialization The first few instructions of the kernel must perform critical tasks to ensure the CPU can safely run code. ...