Added VOLS command

Makefile

@@ -5,7 +5,7 @@ LDFLAGS = --config apple2-asm.cfg
 OUTDIR = out
 
 TARGETS = $(OUTDIR)/path.BIN \
-	$(OUTDIR)/bell.CMD $(OUTDIR)/hello.CMD $(OUTDIR)/echo.CMD
+	$(OUTDIR)/bell.CMD $(OUTDIR)/hello.CMD $(OUTDIR)/echo.CMD $(OUTDIR)/vols.CMD
 
 .PHONY: clean all
 all: $(OUTDIR) $(TARGETS)

README.md

@@ -33,6 +33,7 @@ Example:
 /hd/cmds
 ] BELL                   - will invoke /hd/cmds/BELL if present
 ] HELLO                  - will invoke /hd/cmds/HELLO if present
+] VOLS                   - will invoke /hd/cmds/VOLS if present
 ```
 
 Notes:
@@ -43,3 +44,8 @@ Notes:
    * ProDOS BASIC.SYSTEM intrinsics (`CAT`, `PREFIX`, etc)
    * AppleSoft keywords (`LIST`, `PRINT`, etc)
    * CMD files in paths, in listed order
+
+Sample commands:
+* `BELL` - beeps the speaker
+* `HELLO` - shows a short message
+* `VOLS` - lists online volumes (volume name, slot and drive)

package.sh

@@ -21,6 +21,7 @@ add_file "out/path.BIN" "path#062000"
 add_file "out/bell.CMD" "bell#F04000"
 add_file "out/echo.CMD" "echo#F04000"
 add_file "out/hello.CMD" "hello#F04000"
+add_file "out/vols.CMD" "vols#F04000"
 
 rm -r "$PACKDIR"
 

prodos.inc

@@ -4,6 +4,7 @@
 MLI             := $BF00
 
 GET_FILE_INFO   = $C4
+ON_LINE         = $C5
 OPEN            = $C8
 READ            = $CA
 CLOSE           = $CC

vols.cmd.s

@@ -0,0 +1,99 @@
+
+        .include "apple2.inc"
+        .include "prodos.inc"
+
+CROUT           := $FD8E        ; Issue a carriage return.
+COUT            := $FDED        ; Output a character.
+
+        .org    $4000
+
+;;; ============================================================
+
+        ptr := $06
+
+        jsr     CROUT
+
+        MLI_CALL ON_LINE, params
+        bcs     exit
+
+        lda     #<buf
+        sta     ptr
+        lda     #>buf
+        sta     ptr+1
+
+loop:   ldy     #0
+        lda     (ptr),y
+        beq     exit            ; Done!
+
+        ;; Crack drive/slot/name_len
+        and     #%00001111
+        beq     next            ; Error; TODO: if next byte is $57 show Duplicate Volume
+        sta     len
+        lda     (ptr),y
+        and     #%11110000
+        sta     ds
+
+        ;; Print name
+        lda     #'/'|$80        ; Leading slash
+        jsr     COUT
+:       iny
+        lda     (ptr),y         ; Name characters
+        ora     #$80
+        jsr     COUT
+        cpy     len
+        bne     :-
+
+        ;; Space
+        lda     #20
+        sta     CH              ; TODO: COUT spaces, instead of HTAB?
+
+        ;; Slot
+        lda     #'S'|$80
+        jsr     COUT
+        lda     ds
+        and     #%01110000
+        lsr
+        lsr
+        lsr
+        lsr
+        ora     #'0'|$80
+        jsr     COUT
+
+        ;; Drive
+        lda     #','|$80
+        jsr     COUT
+        lda     #'D'|$80
+        jsr     COUT
+        lda     #'1'|$80
+        bit     ds
+        bpl     :+
+        lda     #'2'|$80
+:       jsr     COUT
+        jsr     CROUT
+
+next:   dec     count
+        beq     exit
+
+        clc
+        lda     ptr
+        adc     #16
+        sta     ptr
+        lda     ptr+1
+        adc     #0
+        sta     ptr+1
+        jmp     loop
+
+exit:   rts
+
+;;; ============================================================
+
+.proc params
+param_count:    .byte   2
+unit_num:       .byte   0
+data_buffer:    .addr   buf
+.endproc
+
+count:  .byte   16
+buf:    .res    256
+len:    .byte   0               ; name length
+ds:     .byte   0               ; drive / slot