i seem to have issues with my mips mars snake game, can you fix my code?

################################################################# # Display Configuration # #---------------------------------------------------------------# # Unit Width in pixels: 8 # # Unit Height in Pixels: 8 # # Display Width in Pixels: 512 # # Display Height in Piexels: 256 # #---------------------------------------------------------------# # Total units: (512/8) * (256/8) = 64 x 32 = 2048 pixels # # Arena units: (256/8) * (216/8) = 32 x 27 = 864 pixels # ################################################################# .data # Define Constants SCORE_MAX: .word 864 ARENA_WIDTH: .word 512 ARENA_HEIGHT: .word 256 UNIT_WIDTH: .word 8 UNIT_HEIGHT: .word 8 # Division divu $0, ARENA_WIDTH, UNIT_WIDTH mflo ARENA_UNITS_X divu $0, ARENA_HEIGHT, UNIT_HEIGHT mflo ARENA_UNITS_Y # Multiplication lw $t0, ARENA_UNITS_X lw $t1, ARENA_UNITS_Y multu $t0, $t1 mflo TOTAL_UNITS screenStart: .word 0x10010500 MAX_SCORE: .word SCORE_MAX # Colors SCORE_COLOR: .word 0x00FFFF00 # Yellow ARENA_BG: .word 0xBBBBFFFF # Light Blue APPLE_COLOR: .word 0xFFFF0000 # Red SNAKE_RIGHT: .word 0x0000FF00 # Green SNAKE_DOWN: .word 0x0100FF00 # Dark Green SNAKE_LEFT: .word 0x0200FF00 # Blue SNAKE_UP: .word 0x0300FF00 # Dark Blue # Addresses SCREEN_START: .word 0x10010500 ADD_END_FLAG: .word 0x1fffff0f DOZEN_START: .word 0x10011294, 0x10011298, 0x1001129C, 0x10011394, 0x10011398, 0x1001139C, 0x10011494, 0x10011498, 0x1001149C, 0x10011594, 0x10011598, 0x1001159C, 0x10011694, 0x10011698, 0x1001169C, MAX_SCORE dozen0_start: .word 0x10011294, 0x10011298, 0x1001129C, 0x10011394, 0x1001139C, 0x10011494, 0x1001149C, 0x10011594, 0x1001159C, 0x10011694, 0x10011698, 0x1001169C, 0x1fffff0f dozen1_start: .word 0x1001129C, 0x1001139C, 0x1001149C, 0x1001159C, 0x1001169C, 0x1fffff0f dozen2_start: .word 0x10011294, 0x10011298, 0x1001129C, 0x1001139C, 0x10011494, 0x10011498, 0x1001149C, 0x10011594, 0x10011694, 0x10011698, 0x1001169C, 0x1fffff0f dozen3_start: .word 0x10011294, 0x10011298, 0x1001129C, 0x1001139C, 0x10011494, 0x10011498, 0x1001149C, 0x1001159C, 0x10011694, 0x10011698, 0x1001169C, 0x1fffff0f dozen4_start: .word 0x10011294, 0x1001129C, 0x10011394, 0x1001139C, 0x10011494, 0x10011498, 0x1001149C, 0x1001159C, 0x1001169C, 0x1fffff0f dozen5_start: .word 0x10011294, 0x10011298, 0x1001129C, 0x10011394, 0x10011494, 0x10011498, 0x1001149C, 0x1001159C, 0x10011694, 0x10011698, 0x1001169C, 0x1fffff0f dozen6_start: .word 0x10011294, 0x10011298, 0x1001129C, 0x10011394, 0x10011494, 0x10011498, 0x1001149C, 0x10011594, 0x1001159C, 0x10011694, 0x10011698, 0x1001169C, 0x1fffff0f dozen7_start: .word 0x10011294, 0x10011298, 0x1001129C, 0x1001139C, 0x1001149C, 0x1001159C, 0x1001169C, 0x1fffff0f dozen8_start: .word 0x10011294, 0x10011298, 0x1001129C, 0x10011394, 0x1001139C, 0x10011494, 0x10011498, 0x1001149C, 0x10011594, 0x1001159C, 0x10011694, 0x10011698, 0x1001169C, 0x1fffff0f dozen9_start: .word 0x10011294, 0x10011298, 0x1001129C, 0x10011394, 0x1001139C, 0x10011494, 0x10011498, 0x1001149C, 0x1001159C, 0x1001169C, 0x1fffff0f ################################################################################################# ################################################################################################# # Macros: # _____ .macro Pause li $a0, 100 # li $v0, 32 # Pause for 80 milisec syscall # .end_macro .macro MegaPause li $a0, 500 # li $v0, 32 # Pause for 500 milisec syscall # .end_macro #-----------------------------------------------------------------------------------------------# # __________ .macro PaintArena li $t0, 128 #starting line index [halved line size] li $t1, 0 #starting pixel index lw $t3, screenStart # load starting address on t3 lw $t2, arenaBG #load bg color on t2 drawline: sw $t2, ($t3) # paint pixel_address addi $t3, $t3, 4 # pixel_adress++ addi $t1, $t1, 4 # pixel_i++ blt $t1, $t0, drawline # if pixel_index < (line_size/2), keep painting line addi $t3, $t3, 128 # else, jump pixel_adress to next beginning line. addi $t1, $t1, 128 # jump pixel_i to next beginning line. addi $t0, $t0, 256 # line_i++. ble $t0, 6784, drawline# if not finished painting line, do it again # (27*line_size)+(line_size/2)=6784 .end_macro .macro ScorePlusPlus addi $s0, $s0, 1 .end_macro .macro SaveDispVal move $s1, $t4 # save current unit value move $s2, $t5 # save current dozen value move $s3, $t6 # save current unit value .end_macro .text PaintArena #Paint the arena # Loading starting values... li $s0, 3 # load initial score (size of the initial snake) li $s4, 3 # Head x_pos li $s5, 2 # Head y_pos li $s6, 0x10010704 # Tracking the tail to erase lw $s7, snakeRight # Current movement # for init li $t0, 0x10010704 # Snake begin li $t1, 0x10010710 # Snake end --- total size: (end - begin)/4 li $t4, 0xFFFF0000 # Apple color initialSnake: sw $s7, ($t0) # addi $t0, $t0, 4 # while SB < SE, fill the display with the snake body (size: 6/4??) blt $t0, $t1, initialSnake # initial size will be 2. jal generateApple addi $ra, $ra, 20 # jumps to the line after addi to avoid verification # of self collision (the instruction: beq $t0, 0x0000FF00, quit) jr $ra moveRight: lw $s7, snakeRight jal drawHead addi $s4, $s4, 1 #init line 89 will jump here Pause lw $t7, 0xFFFF0004 # Verifying which key is pressed # OBS: This value stays on the register until another key is pressed beq $t7, 0x00000077, moveUp # w key is pressed beq $t7, 0x00000073, moveDown # s key is pressed beq $t7, 0x00000071, quit # q key is pressed j moveRight moveDown: lw $s7, snakeDown jal drawHead addi $s5, $s5, 1 Pause lw $t7, 0xFFFF0004 # Verifying which key is pressed # OBS: This value stays on the register until another key is pressed beq $t7, 0x00000061, moveLeft # a key is pressed beq $t7, 0x00000064, moveRight # d key is pressed beq $t7, 0x00000071, quit # q key is pressed j moveDown moveLeft: lw $s7, snakeLeft jal drawHead subi $s4, $s4, 1 Pause lw $t7, 0xFFFF0004 # Verifying which key is pressed # OBS: This value stays on the register until another key is pressed beq $t7, 0x00000077, moveUp # w key is pressed beq $t7, 0x00000073, moveDown # s key is pressed beq $t7, 0x00000071, quit # q key is pressed j moveLeft moveUp: lw $s7, snakeUp jal drawHead subi $s5, $s5, 1 Pause lw $t7, 0xFFFF0004 # Verifying which key is pressed # OBS: This value stays on the register until another key is pressed beq $t7, 0x00000061, moveLeft # a key is pressed beq $t7, 0x00000064, moveRight # d key is pressed beq $t7, 0x00000071, quit # q key is pressed j moveUp #-------------------------------------------------------------------------------------------------------------# drawHead: #local reg: t0, t1, t7 # Computing Address of (x, y) on the screen sll $t1, $s5, 6 # t1 = s5 * (2^7) = s5 * 128 (computing y) add $t1, $t1, $s4 # t1 += s4 (computing x) sll $t1, $t1, 2 # (coordenate -> address) lw $t2, screenStart # Start address on the screen add $t1, $t1, $t2 # Terminate couting address of new head lw $t7, ($t1) # Takes data stored at new head for comparation # checking if new head address is valid bne $t7, 0xFFFF0000, checkBG # if next head add is not apple, check if it is BG sw $s7, ($t1) # draw head on bitmap display move $t9, $ra j scoreUp drawHead2: move $ra, $t9 j generateApple # skip tail erasure, and generate apple jr $ra checkBG: bne $t7, 0xBBBBFFFF, quit sw $s7, ($t1) #draw head on bitmap display # and proceed to erase tail #--------------------------------------------------------------------------------------------------------------# eraseTail: #local reg: $t7, $t6, t3 lw $t6, ($s6) # save previous value of tail lw $t7, arenaBG # load arenaBG color sw $t7, ($s6) # Clear the tail on the screen (replace with arena color) lw $t3, snakeRight beq $t6, $t3, eraseRight lw $t3, snakeDown beq $t6, $t3, eraseDown lw $t3, snakeLeft beq $t6, $t3, eraseLeft lw $t3, snakeUp beq $t6, $t3, eraseUp jr $ra eraseRight: addi $s6, $s6, 4 # next pixel to become the tail (x++) jr $ra eraseDown: addi $s6, $s6, 256 # next pixel to become the tail (y++) jr $ra eraseLeft: subi $s6, $s6, 4 # next pixel to become the tail (x--) jr $ra eraseUp: subi $s6, $s6, 256 # next pixel to become the tail (y--) jr $ra #--------------------------------------------------------------------------------------------------------------# generateApple: # Generate random number --------------------------------- li $a1, 1112 # Here $a1 configures the max value wich is the number of units on display (0 til 1023). li $v0, 42 #generates the random number. syscall # Verify if it's inside the playabe area ----------------- move $t0, $a0 # sll $t0, $t0, 2 # Computing new apple address lw $t3, screenStart # add $t3, $t3, $t0 # lw $t0, ($t3) # get new add content bne $t0, 0xBBBBFFFF, generateApple # if new apple address content is not arenaBG, try again # Painting apple pixel ----------------------------------- lw $t0, appleColor sw $t0, ($t3) jr $ra #--------------------------------------------------------- ################################################################################################################ #Calculate Score Units, Dozens and Hundreds -------------------------------------------------------------------- calcScoreDisp: #args: t0. #results: t4, t5, t6 li $t1, 10 li $t2, 100 # Units div $t0, $t1 # div score 10 mfhi $t4 # print (score mod 10) # Dozens: mflo $t7 # score/10 div $t7, $t1 # div (score/10) 10 mfhi $t5 # print ((score/10) mod 10) # Hundreds: div $t6, $t0, $t2 # print (score / 100) jr $ra ############################################################################################### scoreUp: ScorePlusPlus # score++ move $t0, $s0 # move new score to calc Scores to be displayed jal calcScoreDisp beq $s0, 864, quitWin # max score jal paintDisplay SaveDispVal # save display numbers on s1 (units) , s2 (dozens) and s3 (hundreds). j drawHead2 # Paint Switch --------------------------------------------------------------------------------------------------- paintDisplay: move $t8, $ra # save link # prepare Units ------------------------------------------------------------ li $t7, 1 # code 1: painting units jal paintBlack move $t2, $t4 # pass the number to be painted (t4 have the Units) lw $t1, scoreColor # Prepare to paint score color (load color) jal chooseNumber # prepare Dozens ------------------------------------------------------------ # bne $t6, $s2, paintDoz # jr $t8 #only units changed, no need to paint anymore paintDoz: li $t7, 2 # code 2: painting dozens jal paintBlack move $t2, $t5 # pass the number to be painted (t5 = Dozens) lw $t1, scoreColor # Prepare to paint score color (load color) jal chooseNumber # prepare Hundreds ------------------------------------------------------------ # bne $t6, $s3, paintHun # jr $t8 # only changed till dozens, no need to paint anymore paintHun: li $t7, 3 # code 3: painting hundreds jal paintBlack move $t2, $t6 # pass the number to be painted (t6 = Hundred) lw $t1, scoreColor # Prepare to paint score color (load color) jal chooseNumber jr $t8 # finished painting display, go back. # decide what to paint: ------------------------------------------------------------ chooseNumber: #arg: t2, number to be painted beq $t2, 0, paint0 beq $t2, 1, paint1 beq $t2, 2, paint2 beq $t2, 3, paint3 beq $t2, 4, paint4 beq $t2, 5, paint5 beq $t2, 6, paint6 beq $t2, 7, paint7 beq $t2, 8, paint8 j paint9 jr $ra # Paint Number -------------------------------------------------------------------------------------------- paint0: la $t0, dozen0_start # load address from score array start j drawScore_compAdd jr $ra paint1: la $t0, dozen1_start # load address from score array start j drawScore_compAdd jr $ra paint2: la $t0, dozen2_start # load address from score array start j drawScore_compAdd jr $ra paint3: la $t0, dozen3_start # load address from score array start j drawScore_compAdd jr $ra paint4: la $t0, dozen4_start # load address from score array start j drawScore_compAdd jr $ra paint5: la $t0, dozen5_start # load address from score array start j drawScore_compAdd jr $ra paint6: la $t0, dozen6_start # load address from score array start j drawScore_compAdd jr $ra paint7: la $t0, dozen7_start # load address from score array start j drawScore_compAdd jr $ra paint8: la $t0, dozen8_start # load address from score array start j drawScore_compAdd jr $ra paint9: la $t0, dozen9_start # load address from score array start j drawScore_compAdd jr $ra # ------------------ paintBlack: la $t0, dozen_start li $t1, 0 # Display painting -------------------------------------------------------------------------------------------- drawScore_compAdd: # args: (t0, t7, t1) t0 = array_begin_add; t7 = draw_code [1,3]; t1 = color lw $t3, ($t0) # load *array address on t3 beq $t3, 0x1fffff0f , draw_quit # if t3 is end of array, quit # now modify adress (t3) if needed: beq $t7, 1, ds_Unt beq $t7, 2, drawScore_paint subi $t3, $t3, 16 j drawScore_paint ds_Unt: addi $t3, $t3, 16 drawScore_paint: sw $t1, ($t3) # paint pixel *t3 addi $t0, $t0, 4 # advance @array j drawScore_compAdd draw_quit: jr $ra quitWin: quit: add $a0, $zero, $s0 # li $v0, 1 # print score syscall # li $v0, 10 # safe quit syscall #