;---------------------------------------------------------------------------
; simple example that demonstrates how to write to the flash ROM
;---------------------------------------------------------------------------

        !src "../include/gmod3.inc"

        * = $0801
        !word nextline
        !word 2016 
        !byte $9e
        !byte $32, $30, $36, $31
nextline:
        !byte 0,0,0
        jmp start
        
        !src "../lib/gmod3.asm"
        
NOERASE = 0        
ONEPAGE = 0

;-------------------------------------------------------------------------------        

start:
        ;sei

        ; clear screen
        ldx #0
-
        lda #$20
        sta $0400,x
        sta $0500,x
        sta $0600,x
        sta $0700,x
        lda #$01
        sta $d800,x
        sta $d900,x
        sta $da00,x
        sta $db00,x
        inx
        bne -

        ; erase one 64k page
        inc $0404   ; to indicate progress
!if NOERASE = 0 {        
        lda #$00
        jsr flash_erase
}
        
        ; before we can write to the flash, we must erase it
;        inc $0400   ; to indicate progress
;        jsr flash_chiperase
;        inc $0401   ; to indicate progress

;        ldy #0
;--
        ldx #0
-
;        tya
;        pha
        
        txa
        pha

        inc $0405   ; to indicate progress
        
        ; set byte program command and flash address
        pla
        pha
        tax
        lda #0
        sta addr2
        ;ldx #0
        stx addr1
        ;lda #0
        ;sta addr0

        inc $0406   ; to indicate progress
        
        lda #<cart_file_start
cadd:   ldx #>cart_file_start
        ; program one 256byte page
        jsr flash_writepage

        lda cadd+1
        pha
        lsr
        lsr
        lsr
        lsr
        tay
        lda hexdigits,y
        sta $0400
        pla
        and #$0f
        tay
        lda hexdigits,y
        sta $0401        
        
        pla
        tax
;        pla
;        tay

        inc cadd+1
!if ONEPAGE = 0 {
        inx
        cpx #$20    ; number of pages
        bne -
}
       
;         iny
;         cpy #$20
;         bne --

-
        inc $d020
        dec $d020
        jmp -

failure:
        lda #2
        sta $d020
        jmp *

hexdigits:
        !scr "0123456789abcdef"
    
;-------------------------------------------------------------------------------
; align to page boundary so we only have to compare the highbyte of the
; source address in the above loop
        !align 255,0
!if ONEPAGE = 1 {
cart_file_start:
        !for i,0,255 {
        !byte i
        }
} else {
        
        
!if FX = 1 {
cart_file_start:
        !binary "../cartridge-skeleton/gamecart1.bin",$2000
}
!if FX = 2 {
cart_file_start:
        !binary "../cartridge-skeleton/gamecart2.bin",$2000
}

!if FX = 0 {
cart_file_start = $4000
}

}