Beginnigs of CD and ONLINE BASIC.SYSTEM commands.

go

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+ca65 main.asm -t none -l $*
+cl65 main.asm -t none --start-addr 0x2000 --listing 
+cp template.po mydisk.po
+java -jar /Applications/AppleCommander.app/Contents/Resources/Java/AppleCommander.jar -p mydisk.po cd.online BIN 0x2000 < main

main.asm

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+;
+;  main.s
+;  cd-online-basic-system-integration
+;
+;  Created by Rob Greene on 9/14/15.
+;  Copyright (c) 2015 Rob Greene. All rights reserved.
+;
+
+    .PC02   ; Enable 65C02 instructions
+
+; ASCII string with high-bit set, terminated by a zero
+.macro asciizh string
+    .repeat .strlen(string),i
+    .byte .strat(string,i) | $80
+    .endrep
+    .byte 0
+.endmacro
+
+; Dextral (right-most) Character Inverted
+.macro dci string
+    .repeat .strlen(string),i
+    .if .strlen(string) = i
+    .byte .strat(string,i) | $80
+    .else
+    .byte .strat(string,i) & $7f
+    .endif
+    .endrep
+.endmacro
+
+; BASIC.SYSTEM locations:
+
+inbuf       = $0200
+extrncmd    = $be06    ; External command JMP vector
+xtrnaddr    = $be50    ; Execution address of external command
+xlen        = $be52    ; Length of command string-1
+xcnum       = $be53    ; BASIC cmd number (external command = 0)
+pbits       = $be54    ; Parameter bits
+vslot       = $be61
+vdriv       = $be62
+gosystem    = $be70
+sonline     = $bec6    ; BASIC.SYSTEM ONLINE parameter table
+sunitnum    = $bec7
+sbufadr     = $bec8
+getbufr     = $bef5
+
+; MONITOR locations:
+
+crout       = $fd8e
+prbyte      = $fdda
+cout        = $fded
+
+
+    .org $2000
+
+install:
+    lda extrncmd+1
+    sta nextcmd+1
+    lda extrncmd
+    sta nextcmd
+
+    lda #>entry
+    sta extrncmd
+    lda #<entry
+    sta extrncmd
+    rts
+
+    .org $6000
+
+entry:
+    ldx #0
+@again:
+    ldy #0
+:   lda cmdtable,x
+    beq ourcommand
+    cmp inbuf,y
+    bne @nextcmd
+    inx
+    iny
+    bra :-
+@nextcmd:
+    inx
+    lda cmdtable,x
+    bne @nextcmd
+    inx         ; Skip jumps
+    inx
+    lda cmdtable,x
+    bne @again
+
+notOurCommand:
+    sec
+    jmp (nextcmd)
+
+nextcmd: .word 0
+
+ourcommand:
+    stx xlen
+    lda cmdtable,x
+    sta xtrnaddr
+    lda cmdtable+1,x
+    sta xtrnaddr+1
+    stz xcnum
+    lda #$10
+    sta pbits
+    lda #$04
+    sta pbits+1
+    stz vslot
+    stz vdriv
+    clc
+    rts
+
+cmdtable:
+    asciizh "CD"
+    .addr   cd
+    asciizh "ONLINE"
+    .addr   online
+
+;
+; Perform CD command
+;
+cd:
+    rts
+
+;
+; Perform ONLINE command
+; Note we use the input buffer address
+;
+; Buffer format is:
+;   +000 DSSSLLLL    D=Drive, SSS=Slot, LLLL=Length
+;   +001 CHAR1        Name... or error code
+;    ...
+;   +015 CHAR15
+;
+; Output:
+; S7 D1 /HDD
+; S6 D1 Err=$28
+; S5 D1 Err=$57 (S7 D1)
+;
+online:
+    stz sunitnum
+    stz sbufadr
+    lda #>inbuf
+    sta sbufadr+1
+    jsr gosystem
+    bcc @continue
+    rts
+@exit:
+    jmp crout
+
+@continue:
+    ldx #0
+@loop:
+    lda inbuf,x
+    beq @exit
+    jsr printsd     ; Side-effect is to move Acc. to Y-Reg.
+    tya
+    and #$0f
+    beq @deverr
+;    pha
+    tay
+:   inx
+    lda inbuf,x
+    jsr cout
+    dey
+    bne :-
+;    pla
+;    cmp #$0f        ; If string length was 15, already at next entry
+;    beq @loop
+@adjust:
+    jsr crout
+    txa
+    clc
+    adc #$10
+    and #$f0
+    bra @loop
+; A device error message
+@deverr:
+    lda #'E'|$80
+    jsr cout
+    lda #'r'|$80
+    jsr cout
+    jsr cout
+    lda #'='|$80
+    jsr cout
+    inx
+    lda inbuf,x
+    tay             ; short-term save
+    jsr prbyte
+    tya
+    cmp #$57        ; duplicate volume error
+    bne @adjust
+    lda #' '|$80
+    jsr cout
+    lda #'('|$80
+    jsr cout
+    inx
+    lda inbuf,x
+    jsr printsd
+    lda #')'|$80
+    jsr cout
+    bra @adjust
+
+printsd:
+    tay
+    lda #'S'|$80
+    jsr cout
+    tya
+    and #$70
+    lsr
+    lsr
+    lsr
+    lsr
+    ora #'0'|$80
+    jsr cout
+    lda #' '|$80
+    jsr cout
+    lda #'D'|$80
+    jsr cout
+    tya
+    and #$80
+    asl
+    rol
+    ora #'0'|$80
+    jmp cout
+
+