;; #LAYOUT# STD *        #TAKE
;; #LAYOUT# *   KERNAL_0 #TAKE
;; #LAYOUT# *   *        #IGNORE


default_nmi_handler:

	; Implemented according to Computes Mapping the Commodore 64, page 74
	; and to https://www.c64-wiki.com/wiki/Interrupt

	; Save registers, sequence according to Computes Mapping the Commodore 64, page 73
	pha
	+phx_trash_a
	+phy_trash_a

	; XXX: RS-232 support is not implemented

	; XXX confirm NMIs from CIA, or no other NMI will arrive!

!ifdef CONFIG_PLATFORM_COMMODORE_64 {

	jsr cartridge_check
	bne @1
	jmp (ICART_WARM_START)
@1:
}

	; According to C64 Wiki, if STOP key is pressed, the routine assumes warm start request

	; XXX is it right? how to check that IRQ was caused by RESTORE?

	jsr JSTOP
	bcs @2
	jmp return_from_interrupt ; no STOP pressed
@2:
	; STOP + RESTORE - clean the address of the BRK instruction (it is not BRK) first
	lda #$00
	sta CMP0+0
	sta CMP0+1
	jmp (CBINV)