; Platform support library for Neon816
; 

cpu_clk   = 14000000

.proc     _system_interface
          ;wdm 3
          phx
          asl
          tax
          jmp   (table,x)
table:    .addr _sf_pre_init
          .addr _sf_post_init
          .addr _sf_emit
          .addr _sf_keyq
          .addr _sf_key
          .addr _sf_fcode
          .addr _sf_reset_all
.endproc
.export   _system_interface

.proc     _sf_success
          lda   #$0000
          tay
          clc
          rtl
.endproc

.proc     _sf_fail
          ldy   #.loword(-21)
          lda   #.hiword(-21)
          sec
          rtl
.endproc


.proc     _sf_pre_init
          plx
          jmp   _sf_success     ; we'll see what we need to do
.endproc

.proc     _sf_post_init
          plx
          jmp   _sf_success
.endproc

.proc     _sf_emit
          plx                   ; get forth SP
          jsr   _popay          ; grab the top item
          phx                   ; and save new SP
          ; TODO: interact with the hardware here
          plx
          jmp   _sf_success
.endproc

.proc     _sf_keyq
          ldy   #$0000          ; anticipate false
          ; TODO: interact with the hardware here, set y to FFFF if char available
          tya
          plx
          jsr   _pushay
          jmp   _sf_success
.endproc

.proc     _sf_key
          ; TODO: interact with hardware, wait for char, get it into Y
          lda   #$0000
          plx
          jsr   _pushay
          jmp   _sf_success
.endproc

.proc     _sf_fcode
.if include_fcode
          ldy   #.loword(list)
          lda   #.hiword(list)
.else
          lda   #$0000
          tay
.endif
          plx
          jsr   _pushay
          jmp   _sf_success
.if include_fcode
list:
          .dword 0
.endif
.endproc

; TODO....
.proc     _sf_reset_all
          plx
          jmp   _sf_fail
.endproc