base.asm

* = HRESET
                CLC
                XCE   ; go into native mode
                SEI   ; ignore interrupts
                JML GAME_START
                
* = HIRQ       ; IRQ handler.
RHIRQ
                .as
                .xl
                PHB
                PHD
                PHA
                PHX
                PHY
                ;
                ; todo: look up IRQ triggered and do stuff
                ;
                JSL IRQ_HANDLER

                PLY
                PLX
                PLA
                PLD
                PLB
                RTI
                
; Interrupt Vectors
* = VECTORS_BEGIN
JUMP_READY      JML GAME_START ; Kernel READY routine. Rewrite this address to jump to a custom kernel.
RVECTOR_COP     .addr HCOP     ; FFE4
RVECTOR_BRK     .addr HBRK     ; FFE6
RVECTOR_ABORT   .addr HABORT   ; FFE8
RVECTOR_NMI     .addr HNMI     ; FFEA
                .word $0000    ; FFEC
RVECTOR_IRQ     .addr HIRQ     ; FFEE

RRETURN         JML GAME_START

RVECTOR_ECOP    .addr HCOP     ; FFF4
RVECTOR_EBRK    .addr HBRK     ; FFF6
RVECTOR_EABORT  .addr HABORT   ; FFF8
RVECTOR_ENMI    .addr HNMI     ; FFFA
RVECTOR_ERESET  .addr HRESET   ; FFFC
RVECTOR_EIRQ    .addr HIRQ     ; FFFE