From 0fb47ca39e30d9e6ea68f1d254df12bb3f516863 Mon Sep 17 00:00:00 2001
From: Peter Ferrie <peter.ferrie@gmail.com>
Date: Mon, 11 Mar 2019 17:41:52 -0700
Subject: [PATCH] support Bug Attack, disable IIGS boot timeout

---
 res/notes.txt      |  6 ------
 src/anti-m.a       |  7 ++++++-
 src/idbroderbund.a | 41 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 47 insertions(+), 7 deletions(-)

diff --git a/res/notes.txt b/res/notes.txt
index 4153444..48ded90 100644
--- a/res/notes.txt
+++ b/res/notes.txt
@@ -1,8 +1,2 @@
 Untested (Gebelli):
 - Lazer Silk
-
-Do not work yet:
-- Bug Attack (Cavalier)
-  $A2BB: 4C D4 A2 to bypass undocumented 6502 opcodes
-  $A2F6: 4C 36 4D to bypass undocumented 6502 opcodes and 6502-specific JMP behavior
-  ...TODO there are more undocumented opcodes
diff --git a/src/anti-m.a b/src/anti-m.a
index 985084b..0c01d2c 100644
--- a/src/anti-m.a
+++ b/src/anti-m.a
@@ -70,7 +70,12 @@ Boot
          sta   $1600,x
          inx
          bne   -
-         lda   #<Tracer
+         lda   $1658
+         cmp   #$D0
+         bne   +
+         lda   #$80                  ; BRA on IIGS to disable timeout
+         sta   $1658
++        lda   #<Tracer
          ldx   #>Tracer
          ldy   $16F8
          cpy   #$4C
diff --git a/src/idbroderbund.a b/src/idbroderbund.a
index 1eeb91d..18aad0c 100644
--- a/src/idbroderbund.a
+++ b/src/idbroderbund.a
@@ -2,6 +2,7 @@
 ; written by 4am and qkumba
 ;
 ; tested on
+; - Bug Attack (Cavalier)
 ; - Choplifter (Broderbund)
 ; - David's Midnight Magic (Broderbund)
 ; - Dueling Digits (Broderbund)
@@ -244,6 +245,10 @@ IDBroderbund
          ldx   #<@StarThiefCallback
          ldy   #>@StarThiefCallback
          cmp   #$41
+         beq   @hookhybrid
+         ldx   #<@BugAttackCallback
+         ldy   #>@BugAttackCallback
+         cmp   #$A1
          bne   +
 
 @hookhybrid
@@ -338,3 +343,39 @@ IDBroderbund
          lda   #$68
          sta   $42C2
          jmp   $4200
+
+@BugAttackCallback
+         ldy   #@BugAttackCallback2_e-@BugAttackCallback2
+-        lda   @BugAttackCallback2-1,y
+         sta   @BugAttackCallback2x-1,y
+         dey
+         bne   -
+         lda   #$4C
+         sta   $A2BB
+         lda   #$D4
+         sta   $A2BC
+         lda   #$A2
+         sta   $A2BD
+         lda   #$4C
+         sta   $A2F6
+         lda   #<@BugAttackCallback2x
+         sta   $A2F7
+         lda   #>@BugAttackCallback2x
+         sta   $A2F8
+         jmp   $A200
+
+@BugAttackCallback2 !pseudopc $110 {
+@BugAttackCallback2x
+         lda   #$16
+         sta   $4E06
+         lda   #$4C
+         sta   $4A78
+         lda   #$A4
+         sta   $4A79
+         lda   #$49
+         sta   $4A7A
+         lda   #$87
+         sta   $EB5
+         jmp   $4D36
+}
+@BugAttackCallback2_e
\ No newline at end of file