# HG changeset patch
# User Robert McIntyre <rlm@mit.edu>
# Date 1346492561 18000
# Node ID df3a7eac39d7272693f6210339e9219aac72b84d
# Parent  376f282bcbf12998ba6cfb47e9d504504722bc9d
saving progress.

diff -r 376f282bcbf1 -r df3a7eac39d7 clojure/com/aurellem/run/adv_choreo.clj
--- a/clojure/com/aurellem/run/adv_choreo.clj	Sat Sep 01 04:19:15 2012 -0500
+++ b/clojure/com/aurellem/run/adv_choreo.clj	Sat Sep 01 04:42:41 2012 -0500
@@ -128,11 +128,8 @@
 
  
 (defn glyph-display-program
-  [start-address
-   max-glyphs]
+  [start-address]
   (let [data-start (+ 2 start-address)
-        [max-glyphs-high max-glyphs-low]
-        (disect-bytes-2 max-glyphs)
         load-data
         (flatten
          [;; data region
@@ -144,35 +141,23 @@
 
           ;; load data from data region into registers
 
-          0xF5 ;; push A
-          0x21 ;; begin data load
+          0xF5 ;; push A, which contains current glyph
+
+          0x21
           (reverse (disect-bytes-2 data-start))
-          
-          0x2A 0x47 ;; glyphs-rendered -> BC 
-          0x2A 0x4F 
+          ;; load row and column into DE
+          0x2A 0x57 ;; row -> D
+          0x2A 0x5F ;; column -> E
 
-          0x16 max-glyphs-high  ;; load max-glyphs 
-          0x1E max-glyphs-low   ;; into DE
+
           ])
 
 
         display-glyph
         (let [init*
               (flatten
-               [;; BC is current number of glyphs rendered.
-                ;; each glyph is two characters, and the screen can hold up
-                ;; to 360 characters. Thus, if the current glyphs is a
-                ;; multiple of 180, the screen must be refreshed.
-
-                ;; DE contains max-glyphs and HL will be overwritten next
-                ;; section, so both are free to use here.
-                (repeat 100 0)
+               [(repeat 100 0)
                 ;; Reset HL to initial value
-                0x21
-                (reverse (disect-bytes-2 data-start))
-                ;; load row and column into DE
-                0x2A 0x57 ;; row -> D
-                0x2A 0x5F ;; column -> E
 
                 ;; clear screen if we are at 0,0
                 0x57 0xB3 ;; D->A, OR E A ==> (= D E 0)
@@ -210,6 +195,8 @@
                 ;; restore all registers
                 0xF1 0xE1 0xD1 0xC1])
 
+              ;; RLM: for TESTING ONLY!!!
+              clear-screen (repeat 10 0)
               increment-row-column
               [;; D contains row and E contains column
                
@@ -230,45 +217,48 @@
                
               set-HL-from-row-and-column
               [;; formula for memory offset is:
-               ;; (+ 0x9800 (* 32 row) column)
+               ;; (+ 0x9800 (* 32 row) column) == 
+               ;; (+ 0x97E0 (* 32 (+ 1 row)) column)
                0xD5 0xC5 ;; push D E B C
 
-               0x21 0x00 0x98 ;; load HL with 0x9800
+               0x21 0xE0 0x97 ;; load HL with 0x97E0
+               
+               0x06 0
+               0x0E 32     ;; load 32 into BC
 
-               0x01 32 00  ;; load 32 into BC
+               0x14 ;; inc D to handle case where D == 0
+               ;; D will never be > 20, so this will never overflow.
 
                ;; do 
-               0x09 ;; HL += 32
-               0x15 ;; dec D
+                 0x09 ;; HL += 32
+                 0x15 ;; dec D
                ;; while D != 0
                0x20 
                (->signed-8-bit -4)
-
-               0x4B ;; E->C
-               0x15 ;; add columns (E) to HL
-
+               
                0xC1 0xD1 ;; pop C B E D
                ]
               
               render-glyph
               (flatten
-               [set-HL-from-row-and-column
+               [;; Render each nybble of A as a character
+                ;; there are two characters to a glyph.
+               
+                set-HL-from-row-and-column
                 0xF1 ;; pop A, now A is equal to key input
                 0xF5 ;; save A
 
                 0xE6 0xF0 ;; clear second nybble
                 0xCB 0x37 ;; swap nybbles
-                0x22 ;; store A in video as a character (pun)
-
+                0x22 ;; store A in video RAM as a character (pun)
+                increment-row-column
+                
+                set-HL-from-row-and-column
                 0xF1 ;; restore A
                 0xE6 0x0F ;; select second nybble
-                0x22 ;; store second nybble as glyph
-               
+                0x22 ;; store second nybble as character
                 increment-row-column
-                increment-row-column
-                ;; Render each nybble of A as a character
-                ;; there are two characters to a glyph.
-                ])
+                 ])
 
               
               init (replace
@@ -304,8 +294,7 @@
         glyph-display (glyph-display-program
                        (+ (count init)
                           (count header)
-                          start-address)
-                       2000)
+                          start-address))
                        ;;(- (count (program-data 0)) 100))
 
         state-machine-start-address