work around unpatchable CFFA firmware bug

src/constants.a

@@ -143,10 +143,10 @@ SUPPORTS_SHR   = %00110000
 CHEATS_ENABLED = %00001000
 
 ; shared symbols
-iProDOS_enter  = $D66E
-LoadFileDirect = $DAFA
-launchpatch    = $D613
+iProDOS_enter  = $D678
+LoadFileDirect = $DB01
+launchpatch    = $D616
 iAddToPath     = $FEC3
-itraverse      = $D8D9
+itraverse      = $D8E0
 namlo          = $57
 namhi          = $58

src/prodos.impl.lc2.a

@@ -169,10 +169,7 @@ ProDOS_enter
          lda   ldrlo2+1
          sta   (ipacket), y
          ldy   #$13
-         lda   (scratchlo), y
-         tax
-         iny
-         lda   (scratchlo), y
+         jsr   fetchscratch
          ldy   #9
          sta   (ipacket), y
          txa

src/prorwts2.a

@@ -1037,32 +1037,20 @@ foundname       iny
 
   !if override_adr = 0 {
                 ldy     #AUX_TYPE
-                lda     (scratchlo), y
-    !if (allow_subdir + allow_saplings + allow_trees + (aligned_read xor 1)) > 0 {
-                sta     ldrlo
-                iny
-                lda     (scratchlo), y
+                jsr     fetchscratch
+                stx     ldrlo
                 sta     ldrhi
-    } else { ;allow_subdir = 0 and allow_saplings = 0 and allow_trees = 0 and aligned_read = 1
-                pha
-                iny
-                lda     (scratchlo), y
-                pha
-    } ;allow_subdir = 1 or allow_saplings = 1 or allow_trees = 1 or aligned_read = 0
   } ;override_adr = 0
 
                 ;cache KEY_POINTER
 
                 ldy     #KEY_POINTER
-                lda     (scratchlo), y
-                tax
+                jsr     fetchscratch
   !if (allow_subdir + allow_saplings + allow_trees) > 0 {
-                sta     dirbuf
+                stx     dirbuf
     !if (allow_trees + (fast_trees xor 1)) > 1 {
-                sta     treeblklo
+                stx     treeblklo
     } ;allow_trees = 1 and fast_trees = 0
-                iny
-                lda     (scratchlo), y
                 sta     dirbuf + 256
     !if (allow_trees + (fast_trees xor 1)) > 1 {
                 sta     treeblkhi
@@ -3237,8 +3225,11 @@ hddwriteimm     lda     adrhi ;for Trackstar support
                 jsr     saveslot
 } ;swap_scrn = 1
 
+                php
+                sei
 unrentry = unrelochdd + (* - reloc)
                 jsr     $d1d1
+                plp
 !if use_smartport = 1 {
 unrpcommand = unrelochdd + (* - reloc)
 pcommand        !byte   $2c ;hide packet in non-SmartPort mode
@@ -3283,6 +3274,13 @@ initpatch       lda     ($48), y
 } ;swap_scrn = 1
                 rts
 
+fetchscratch
+                lda     (scratchlo), y
+                tax
+                iny
+                lda     (scratchlo), y
+                rts
+
 !if use_smartport = 1 {
 unrpacket = unrelochdd + (* - reloc)
 packet          !byte   3