add support for SRA protection check hidden in character generator

src/passport.a

@@ -762,6 +762,7 @@ _applyToAll
          !source "patchers/advint.a"            ; gAdventureInternational only
          !source "patchers/jsr8635.a"           ; gIsRWTS only
          !source "patchers/dos32jmpb4bb.a"      ; T01 && gIsDOS32 only
+         !source "patchers/sra.a"               ; gIsDOS32 or gIsRWTS only
 
          lda   gPatchCount
          beq   .nopatches

src/patchers/sra.a

@@ -0,0 +1,43 @@
+;-------------------------------
+; #SRA
+; nibble check hidden inside character generator (file named MPG CODE)
+; seen on 13- and 16-sector disks by Science Research Associates
+;
+; tested on
+; Decimals C-2 (1981, SRA)
+; Decimals C-3 (1981, SRA)
+; Fractions C-2 (1981, SRA)
+; Fractions C-3 (1981, SRA)
+; Multiplication B (1981, SRA)
+; Measurement D-1 (1983, SRA)
+;-------------------------------
+!zone {
+         lda   gIsDOS32
+         bne   +
+         lda   #$0C
+         bne   .start                ; always branches
++        lda   gIsBoot0
+         bne   .exit
+         lda   #$0F
+.start   sta   .sector+1
+.sector  lda   #$FF                  ; modified above
+         sta   gDisplayBytes
+         ldx   #$3A
+         ldy   #$09
+         jsr   compare
+         !byte $20,$00,$7B           ; JSR $7B00
+         !byte $8D,$6C,$7A           ; STA $7A6C
+         !byte $AD,$B1,$78           ; LDA $78B1
+         bcs   .nextsector
+         lda   #s_sra
+         jsr   PrintByID
+         lda   .sector+1
+         inx
+         ldy   #$02
+         jsr   modify
+         !byte $0F,$5A               ; new JSR entry point
+.nextsector
+         dec   .sector+1
+         bpl   .sector
+.exit
+}

src/strings/en.a

@@ -108,7 +108,8 @@ s_dos32b0 =    $59
 s_bootwrite =  $5A
 s_rwtswrite =  $5B
 s_rdos =       $5C
-STRINGCOUNT =  $5D
+s_sra =        $5D
+STRINGCOUNT =  $5E
 
 !zone {
 StringTable
@@ -205,6 +206,7 @@ StringTable
          !word .bootwrite
          !word .rwtswrite
          !word .rdos
+         !word .sra
 ;
 ; Text can contain substitution strings, which
 ; are replaced by current values at runtime. Each
@@ -230,7 +232,7 @@ StringTable
 ; can be set directly before calling PrintByID.
 ;
 .header
-         !text "Passport by 4am               2017-10-01",$00
+         !text "Passport by 4am               2017-10-06",$00
 .mainmenu
          !text "________________________________________",$8D,$8D,$8D,$8D,$8D,$8D,$8D
          !text "              "
@@ -510,4 +512,6 @@ StringTable
          !text "T00,S02 Writing built-in RWTS",$8D,$00
 .rdos
          !text "T00,S00 Found RDOS bootloader",$8D,$00
+.sra
+         !text "T%t,S%0 Found SRA protection check",$8D,$00
 }