improved DOS 3.3 Launcher support

DOS33L.S

@@ -0,0 +1,41 @@
+;qboot DOS 3.3 default launcher support
+;copyright (c) Peter Ferrie 2016
+;assemble using ACME
+!cpu 6502
+!to "dos33l",plain
+;place on sector 1
+*=$BF00
+        stx     sectors
+        sta     address
+        lda     phase
+        lsr
+        sta     track
+-       sty     index + 1
+        lda     xlatsec, y
+        sta     sector
+        lda     #>iocb
+        ldy     #<iocb
+        jsr     $bd00
+index   ldy     #0
+        iny
+        tya
+        and     #$0f
+        tay
+        bne     +
+        inc     track
++       inc     address
+        bcc     +
+phase   !byte   $d1 ;set by bootsector if qboot loaded to $be00
++       dec     sectors
+        bne     -
+        rts
+
+sectors !byte   $d1
+xlatsec !byte   0, 7, $e, 6, $d, 5, $c, 4, $b, 3, $a, 2, 9, 1, 8, $f
+iocb    !byte   1, $60, 1, 0
+track   !byte   $d1
+sector  !byte   $d1
+        !byte   <dct, >dct, 0
+address !byte   $d1
+        !byte   0, 0, 1, 0, 0, $60, 1
+dct     !byte   1, $ef, $d8, 0

DOS33LR.S

@@ -0,0 +1,38 @@
+;qboot DOS 3.3 relocated launcher support
+;copyright (c) Peter Ferrie 2016
+;assemble using ACME
+!cpu 6502
+!to "dos33l",plain
+;place on sector 1
+*=$BF00
+        firsttrk  = $d1         ;user-defined, first track to read
+
+        stx     sectors
+        sta     address
+-       sty     index + 1
+        lda     xlatsec, y
+        sta     sector
+        lda     #>iocb
+        ldy     #<iocb
+        jsr     $bd00
+index   ldy     #0
+        iny
+        tya
+        and     #$0f
+        tay
+        bne     +
+        inc     track
++       inc     address
+        dec     sectors
+        bne     -
+        rts
+
+sectors !byte   $d1
+xlatsec !byte   0, 7, $e, 6, $d, 5, $c, 4, $b, 3, $a, 2, 9, 1, 8, $f
+iocb    !byte   1, $60, 1, 0
+track   !byte   firsttrk
+sector  !byte   $d1
+        !byte   <dct, >dct, 0
+address !byte   $d1
+        !byte   0, 0, 1, 0, 0, $60, 1
+dct     !byte   1, $ef, $d8, 0

QBOOT.S

@@ -1,5 +1,5 @@
 ;fast seek/multi-read
-;copyright (c) Peter Ferrie 2015
+;copyright (c) Peter Ferrie 2015-16
 ;assemble using ACME
 !cpu 6502
 !to "qboot",plain
@@ -67,6 +67,10 @@
         ldy     #$7f
         bne     +               ;branch always
 *=$839
+        lda     #>(entry-1)
+        pha
+        lda     #<(entry-1)
+        pha
         jsr     preread
         jmp     $bf00           ;DOS 3.3 launcher entrypoint
 
@@ -122,28 +126,42 @@ indextbl        ;the 0 also terminates the patchtbl list!
         iny
         cpy     #3
         bcc     --
-
-preread
-
         lda     #>(entry-1)
         pha
         lda     #<(entry-1)
         pha
+        jsr     preread
+
+!if seekback { ;no room to do this in the routine
+        sty     startsec+1
+        sta     tmpadr+1
+        stx     total+1
+}
+        jmp     seekread
+
+preread
 
 ;copy post-read if necessary
 ;push post-read address here
+;        pla
+;        tax
+;        pla
+;        tay
+;        lda     #>(postread-1)
+;        pha
+;        lda     #<(postread-1)
+;        pha
+;        tya
+;        pha
+;        txa
+;        pha
 
         lda     #<(firsttrk*2)
         sta     phase+1
         ldx     #sectors
-        ldy     #address
-        lda     #firstsec
-!if seekback { ;no room to do this in the routine
-        sta     startsec+1
-        stx     total+1
-        sty     tmpadr+1
-}
-        jmp     seekread
+        lda     #address
+        ldy     #firstsec
+        rts
 
 *=$8fe
         !byte   $be, 1
@@ -163,9 +181,9 @@ slotpatch1
 
 seekread
 !if seekback=0 {
-        sta     startsec+1
+        sty     startsec+1
+        sta     tmpadr+1
         stx     total+1
-        sty     tmpadr+1
 }
 
 inittrk