# HG changeset patch
# User Robert McIntyre <rlm@mit.edu>
# Date 1333168798 18000
# Node ID 1de6aada1cb78a0c8707bfcc5df9b649c7816f66
# Parent  bc1f62b269b51d0b7438006ef223cef42b83546f
inserted backwards jump into bootstrap program to fit it into item-pc space

diff -r bc1f62b269b5 -r 1de6aada1cb7 clojure/com/aurellem/exp/notes.txt
--- a/clojure/com/aurellem/exp/notes.txt	Fri Mar 30 23:05:38 2012 -0500
+++ b/clojure/com/aurellem/exp/notes.txt	Fri Mar 30 23:39:58 2012 -0500
@@ -2,7 +2,7 @@
 
 start game
 
-name rival "L<PK>T<PK>" 
+name rival "L<PK>T<PK><PK><any-character>" 
 (0x8B 0xE1 0x93 0xE1 in character codes)
 
 get pikachu, fight rival, deliver oak's parcel, go back to
@@ -29,30 +29,15 @@
 pattern in the item computer.  You can do this with what is
 in your item list because of the previous setup.
 
-[repeat following 35 times]
+[repeat the following 24 times]
 0xFF	
 0x01
 [end repeat]
 
-;;; program to swap item ID and quantity at fixed address.
-;; here target is equal to rival's thrid and fourth character
+;; Second part of program to swap item ID and quantity at
+;; fixed address.
 
-0x00
-0x21  ;; load target into HL
-
-third rival's name character
-xD5     -- target item address
-
-0x00
-0x18  ;; jump relative
-
-pokeball ;; pokeball = 0x04, so
-x any    ;; jump over the next four bytes
-
-target-item type
-target-item quantity
-
-0x00
+0x00  ;; this starts at address 0xD56C
 0x2A  ;; save (HL)=(target) to A, increment HL
 
 0x00
@@ -63,7 +48,7 @@
 
 0x00
 0x22  ;; save A to target, increment HL [(target+1) -> target]
-
+ 
 0x00
 0x70  ;; load B into target+1 [(target) -> target+1]
 
@@ -73,8 +58,29 @@
 burn-heal
 x 95          -- address of Route 3 memory-function
 
+[repeat the following 8 times]
+0xFF
+0x01
+[end repeat]
 
-Drop enough from rival's first character/ second character
+0x00  ;; this starts at address 0xD58B
+0x21  ;; load target into HL
+
+third rival's name character
+x D5     -- target item address
+
+0x00
+0x18  ;; jump relative
+
+fifth rival's name character (PK) (TM25) (0xE1 == -31)
+x any
+
+target-item type
+target-item quantity
+
+
+
+Drop enough from rival's first character/ third character
 as an item so that it is [_ 0xD5] instead of [_ 0xE1].
 
 shift rival's name's first two characters into
@@ -136,3 +142,13 @@
    0x9B   ")" ;          [x]
    0x9C   ":" ;          [x]
     --- last valid character for target
+
+
+
+;;; character canadates for jump-relative backwards
+
+   0xE1   "PK" ;          [TM25]
+   0xE2   "MN" ;          [TM26]
+   0xE6   "?"  ;          [TM30]
+   0xE7   "!"  ;          [TM31]
+   0xE8   "."  ;          [TM32]
diff -r bc1f62b269b5 -r 1de6aada1cb7 clojure/com/aurellem/gb/util.clj
--- a/clojure/com/aurellem/gb/util.clj	Fri Mar 30 23:05:38 2012 -0500
+++ b/clojure/com/aurellem/gb/util.clj	Fri Mar 30 23:39:58 2012 -0500
@@ -218,3 +218,13 @@
          descriptions))))
   ([] (print-D-memory @current-state)))
   
+
+(defn signed-8-bits
+  "the lower 8 bits of an integer interpreted as a signed 8
+   bit number"
+  [n]
+  (let [lower-seven (bit-and n 127)]
+    (if (bit-test n 7)
+      (- 128 lower-seven)
+      lower-seven)))
+  
\ No newline at end of file