shave some bytes

src/initscan.a

@@ -13,7 +13,11 @@ RAMFileName_e
 ;        all registers and flags clobbered
 ;-------------------------------
 ScanForDiskII
+         ldx   #$06
          lda   #$00
+-        sta   DiskIIArray, x
+         dex
+         bpl   -
          sta   cmp1
          ldx   #$07
 -        txa
@@ -49,7 +53,11 @@ ScanForDiskII
 ;        all registers and flags clobbered
 ;-------------------------------
 ScanForRAMAndHardDisks
+         ldy   #14
          lda   #$00
+-        sta   HardDiskArray, y
+         dey
+         bpl   -
          sta   iunit
 @nextunit
          lda   iunit

src/memory.a

@@ -2,6 +2,8 @@
 ; YE OLDE GRAND UNIFIED MEMORY MAP
 ;
 ; 02D8..038D - clobbered by Optimum reader
+; 038E..0394 - DiskIIArray
+; 0395..03A3 - HardDiskArray
 ; 0800..08FF - clobbered by all boot tracers and RAM disk
 ; 0900..09FF - clobbered by Special Delivery tracer and RAM disk
 ; 0A00..0AFF - backup of zero page during Special Delivery tracer, used by RAM disk

src/passport.a

@@ -446,9 +446,9 @@ _byte_skip_hi:
          !source "id/panglosdos.a"
          !source "id/davidson.a"
          !source "id/holle.a"
-         !source "id/bootfailure.a"
          !source "id/phoenix.a"
          !source "id/555.a"
+         !source "id/bootfailure.a"
          !source "print.a"
          !source "compare.a"
          !source "modify.a"

src/slots.a

@@ -1,7 +1,5 @@
-DiskIIArray
-         !fill 7
-HardDiskArray
-         !fill 15
+DiskIIArray = $038E
+HardDiskArray = $0395
 
 ;-------------------------------
 ; NextSlot
@@ -11,26 +9,22 @@ HardDiskArray
 ;        @gTargetType set based on type of target (see apidefs.a for values)
 ;-------------------------------
 NextSlot
-         lda   DRIVE
-         cmp   #$31
+         ldy   #$31
+         cpy   DRIVE
          bne   NextSlotLoop
-         lda   #$32                  ; cycle from drive 1 to drive 2 of the same slot
-         sta   DRIVE
+         inc   DRIVE                 ; cycle from drive 1 to drive 2 of the same slot
          bne   ThisSlot              ; always branches
 NextSlotLoop
-         lda   #$31                  ; cycle to drive 1 of the next slot
-         sta   DRIVE
+         sty   DRIVE                 ; cycle to drive 1 of the next slot
          inc   SLOT
 ThisSlot
          lda   SLOT
          cmp   #$38
          bne   +
-         lda   #$31                  ; cycle from slot 7 back to slot 1
-         sta   SLOT
-+        sec
-         sbc   #$30
-         tax
-         lda   DiskIIArray-1, x
+         sty   SLOT                  ; cycle from slot 7 back to slot 1
+         tya
++        tax
+         lda   DiskIIArray-$31, x
          beq   @maybeHardDisk
 
          lda   SLOT
@@ -71,6 +65,7 @@ LookupUnitNumberOfSelectedHardDisk
 ;          then A=ProDOS unit number, Z=0
 ;        otherwise A=0, Z=1
 ;        X clobbered
+;        Y preserved
          lda   SLOT
          sec
          sbc   #$30