.segment "EXTRA"

; IO

CHKIN:
        stx CURDVC
        stx IO_FILE_DESCRIPTOR
        lda IO_COMMAND_SELECT_IN
        sta IO_FILE_COMMAND
        rts

CHKOUT:
        stx CURDVC
        stx IO_FILE_DESCRIPTOR
        lda IO_COMMAND_SELECT_OUT
        sta IO_FILE_COMMAND
        rts

CLRCH:
        lda #0
        sta CURDVC
        lda IO_COMMAND_RESET
        sta IO_FILE_COMMAND
        rts

CHRIN:
        lda CURDVC
        bne @file
        lda IO_KBD
        bmi @end
        jsr CHROUT ; echo
@file:
        lda IO_COMMAND_READ
        sta IO_FILE_COMMAND
@wait:
        lda IO_FILE_STATUS
        and #FILE_STATUS_READY
        beq @wait
        lda IO_FILE_DATA
@end:
        rts

CHROUT:
        lda CURDVC
        bne @file
        sta IO_SCREEN
        rts
@file:
        sta IO_FILE_DATA
        lda IO_COMMAND_WRITE
        sta IO_FILE_COMMAND
@wait:
        lda IO_FILE_STATUS
        and #$4
        beq @wait
        rts

OPEN:
        jsr GETBYT
        stx IO_FILE_DESCRIPTOR
        jsr CHKCOM
        jsr FRMEVL
        jsr CHKSTR
        jsr FREFAC
        sta STRNG2
        ldy #0
@copy:
        cpy STRNG2
        beq @done_copy
        lda (INDEX),y
        sta FILE_NAME_BUFFER,y
        iny
        bne @copy
@done_copy:
        lda #0
        sta FILE_NAME_BUFFER,y
        lda #<FILE_NAME_BUFFER
        sta IO_FILE_DATA
        lda #>FILE_NAME_BUFFER
        sta IO_FILE_DATA+1
        lda #IO_COMMAND_OPEN
        sta IO_FILE_COMMAND
@wait:
        lda IO_FILE_STATUS
        and #FILE_STATUS_READY
        beq @wait
        lda #FILE_STATUS_READY
        and #$01
        bne @error
        rts
@error:
        jmp     IQERR

CLOSE:
        rts

; Default

ISCNTC:
        lda IO_KBD
        cmp #$03
        beq :+
        rts
:
        jmp STOP

SYS:
        jsr GTNUM
        lda LINNUM
        sta SYSJMP+1
        lda LINNUM+1
        sta SYSJMP+2
SYSJMP:
        jsr $FFFF
        rts

MONRDKEY := CHRIN
MONCOUT  := CHROUT

.segment "WOZMON"
.include "wozmon.s"

.segment "RESETVEC"
.word   $0000           ; NMI vector
.word   COLD_START      ; RESET vector
.word   $0000           ; IRQ vector