Mercurial > vba-clojure

     1 (ns com.aurellem.gb.dylan-assembly

     2   "A much more compact version of write-memory-assembly"

     3   {:author "Dylan Holmes"}

     4   (:use (com.aurellem.gb gb-driver assembly util))

     5   (:import [com.aurellem.gb.gb_driver SaveState]))

     6 

     7 (defn write-memory-assembly-compact

     8   "Currently, grabs input from the user each frame."

     9   []

    10   [

    11    ;; --------- FRAME METRONOME

    12    0x18 ;; jump ahead to cleanup. first time only.

    13    0x40 ;; v-blank-prev [D31E]

    14 

    15    0xFA ;; load modes into A [D31F]

    16    0x41

    17    0xFF

    18 

    19    0x47 ;; A -> B

    20    0xCB ;; rotate A

    21    0x2F

    22    0x2F ;; invert A

    23 

    24    0xA0

    25    0x47 ;; now B_0 contains (VB==1)

    26 

    27    0xFA ;; load v-blank-prev

    28    0x1E

    29    0xD3

    30 

    31    0x2F ;; complement v-blank-prev

    32    

    33    0xA0 ;; A & B --> A

    34    0x4F ;; now C_0 contains increment?

    35 

    36 

    37    0x78 ;; B->A

    38    0xEA ;; spit A --> vbprev

    39    0x1E

    40    0xD3

    41 

    42    0xCB   ;test C_0

    43    0x41

    44    0x20   ; JUMP ahead to button input if nonzero

    45    0x02

    46    0x18   ; JUMP  back to frame metronome (D31F)

    47    0xE7

    48    

    49    ;; -------- GET BUTTON INPUT

    50 

    51         ;; btw, C_0 is now 1

    52         ;; prepare to select bits

    53 

    54    0x06 ;; load 0x00 into B

    55    0x00 ;; to initialize for "OR" loop

    56  

    57    0x3E ;; load 0x20 into A, to measure dpad

    58    0x20

    59 

    60    

    61    0xE0 ;; load A into [FF00] ;; start of OR loop [D33C]

    62    0x00

    63    

    64    0xF0 ;; load A from [FF00]

    65    0x00

    66 

    67    0xE6 ;; bitmask 00001111

    68    0x0F

    69    

    70    0xB0 ;; A or B --> A

    71    0xCB

    72    0x41 ;; test bit 0 of C

    73    0x28 ;; JUMP forward if 0

    74    0x08

    75 

    76    0x47 ;; A -> B

    77    0xCB ;; swap B nybbles

    78    0x30 

    79    0x0C ;; increment C

    80    0x3E ;; load 0x10 into A, to measure btns

    81    0x10

    82    0x18 ;; JUMP back to "load A into [FF00]" [20 steps?]

    83    0xED

    84 

    85 

    86    ;; ------ TAKE ACTION BASED ON USER INPUT

    87 

    88    ;; "input mode"

    89    ;; mode 0x00 : select mode

    90    ;; mode 0x08 : select bytes-to-write

    91    ;; mode 0x10 : select hi-bit

    92    ;; mode 0x18 : select lo-bit

    93 

    94    ;; "output mode"

    95    ;; mode 0x20 : write bytes

    96    ;; mode 0xFF : jump PC

    97 

    98 

    99    ;; registers

   100    ;; D : mode select

   101    ;; E : count of bytes to write

   102    ;; H : address-high

   103    ;; L : address-low

   104    

   105    ;; now A contains the pressed keys

   106    0x2F ; complement A, by request. [D34F]

   107    

   108    0x47 ; A->B ;; now B contains the pressed keys

   109    0x7B ; E->A ;; now A contains the count.

   110 

   111    0xCB ; test bit 5 of D (are we in o/p mode?)

   112    0x6A

   113    0x28 ; if test == 0, skip this o/p section

   114    0x13 ; JUMP

   115    

   116    0xCB ; else, test bit 0 of D (fragile; are we in pc mode?)

   117    0x42

   118    0x28 ; if test == 0, skip the following command

   119    0x01

   120 

   121    ;; output mode I: moving the program counter

   122    0xE9 ; ** move PC to (HL)

   123 

   124    ;; output mode II: writing bytes

   125    0xFE ; A compare 0. finished writing?

   126    0x00

   127    0x20 ; if we are not finished, skip cleanup

   128    0x04 ; JUMP

   129 

   130    ;; CLEANUP

   131    ;; btw, A is already zero.

   132    0xAF ; zero A  [D35F]

   133    0x57 ; A->D; makes D=0.

   134    0x18 ; end of frame

   135    0xBC

   136    

   137    ;; ---- end of cleanup

   138 

   139    

   140    ;; continue writing bytes

   141    0x1D ;; decrement E, the number of bytes to write [D363]

   142    0x78 ;; B->A; now A contains the pressed keys

   143    0x77 ;; copy A to (HL)

   144    0x23 ;; increment HL

   145    0x18 ;; end frame. [goto D31F]

   146    0xB6 ;; TODO: set skip length backwards

   147 

   148 

   149    ;; ---- end of o/p section

   150    

   151    ;; i/p mode

   152    ;; adhere to the mode discipline:

   153    ;; D must be one of 0x00 0x08 0x10 0x18.

   154 

   155    0x3E ;; load the constant 57 into A. [D369]

   156    0x57

   157    0x82 ;; add the mode to A

   158    0xEA ;; store A into "thing to execute"

   159    0x74

   160    0xD3

   161 

   162    0x3E ;; load the constant 8 into A

   163    0x08

   164    0x82 ;; add the mode to A

   165    

   166    0x57 ;; store the incremented mode into D

   167    0x78 ;; B->A; now A contains the pressed keys

   168    

   169    0x00 ;; var: thing to execute [D374]

   170 

   171    0x18 ;; end frame

   172    0xA8])

   173 

   174 (defn write-mem-compact []

   175   (-> (tick (mid-game))

   176       (IE! 0)

   177       (inject-item-assembly (write-memory-assembly-compact))))

   178 

   179 (defn drive-compact []

   180   (-> (write-mem-compact)

   181       (#(do (println "memory from 0xC00F to 0xC01F:"

   182                      (subvec (vec (memory %)) 0xC00F 0xC01F)) %))

   183       (step [])

   184       (step [])

   185       (step [])

   186       (step [:start])

   187       (step [:select])

   188       (step [:u :d])

   189       (step [:a :b :start :select])

   190       (step [:a])

   191       (step [:b])

   192       (step [:a :b])

   193       (step [:select])

   194       (step [])

   195       (step [])

   196       (step [])

   197       (#(do (println "memory from 0xC00F to 0xC01F:"

   198                      (subvec (vec (memory %)) 0xC00F 0xC01F)) %))))

   199
author	Robert McIntyre <rlm@mit.edu>
date	Sun, 25 Mar 2012 00:38:45 -0500
parents
children	7c89fe478de4