Snake in arm-like ASM

gistfile1.txt

#define .score r1
#define .var0 r2
#define .var1 r3
#define .count_0 r4
#define .count_1 r5
#define .count_2 r6
#define .head_x r7
#define .head_y r8
#define .tail_x r9
#define .tail_y r10
#define .pomme_x r11
#define .pomme_y r12
&main
ldr count_0, #0
ldr count_1, #0
ldr var0, #0
&clean_start
gmw count_0,count_1,#0	// clean the screen
add count_0,count_0,#1
bcd count_0, var0, $clean_start
add count_1,count_1,#1
bcd count_1,var0, $clean_start
&game_start
ldr head_x,#126
ldr head_y,#128
ldr tail_x,#126
ldr tail_y,#128
gmw tail_x,tail_y,#1	//init the snake (must be an odd length, here: 7)
add tail_x,tail_x,#1
gmw tail_x,tail_y,#1
add tail_x,tail_x,#1
gmw tail_x,tail_y,#1
add tail_x,tail_x,#1
gmw tail_x,tail_y,#1
add tail_x,tail_x,#1
gmw tail_x,tail_y,#1
add tail_x,tail_x,#1
gmw tail_x,tail_y,#1
add tail_x,tail_x,#1
gmw tail_x,tail_y,#1
add tail_x,tail_x,#1
gmw tail_x,tail_y,#1
add tail_x,tail_x,#1
gmw tail_x,tail_y,#1
ldr score,#0			// starting score
&pick_pomme
add r0,tail_y,#157
add lr,pc,#3
push lr
b $rand
ldr pomme_x,r0
and pomme_x,pomme_x,#0xFE		//make it even so the snake can eat it
add lr,pc,#3
push lr
b $rand
ldr pomme_y,r0
and pomme_y,pomme_y,#0xFE		//make it even so the snake can eat it
ldr var0,#1
gmr var1,pomme_x,pomme_y	
gmr var1,pomme_x,pomme_y		//double read for gram
bce var1,var0, $pick_pomme		// pick while it is occupied
gmw pomme_x,pomme_y,#1			// draw apple
&snake_move
ldr count_0,#0
ldr count_1,#0
ldr count_2,#0
ldr var0,#0
ldr var1,#80
sub var1,var1,score				//score changes the speed
&time_div
add count_0,count_0,#1
bcd count_0, var0, $time_div
add count_1,count_1,#1
bcd count_1,var0, $time_div
add count_2,count_2,#1
bcd count_2,var1, $time_div
// actual_snake_move
ldm var0, #0		//load direction
ldm var1, #1		// load previous direction
eor var1, var1,#0b00000010
bcd var1,var0,$keep_on_going
eor var0,var1,#0b00000010
&keep_on_going
stm var0,#1
//chose head_direction_________________
ldr count_0,#0		//future comparison
ldr var1,#0
bce var1,var0,$head_dir_up
ldr var1,#1
bce var1,var0,$head_dir_right
ldr var1,#2
bce var1,var0,$head_dir_down
ldr var1,#3
bce var1,var0,$head_dir_left
&head_dir_up
sub head_y,head_y,#1
gmw head_x,head_y,#1
sub head_y,head_y,#1
gmr var0,head_x,head_y
gmr var0,head_x,head_y
bcd var0,count_0,$deal_with_obstacle
gmw head_x,head_y,#1
b $quit_step_head
&head_dir_right
add head_x,head_x,#1
gmw head_x,head_y,#1
add head_x,head_x,#1
gmr var0,head_x,head_y
gmr var0,head_x,head_y
bcd var0,count_0,$deal_with_obstacle
gmw head_x,head_y,#1
b $quit_step_head
&head_dir_down
add head_y,head_y,#1
gmw head_x,head_y,#1
add head_y,head_y,#1
gmr var0,head_x,head_y
gmr var0,head_x,head_y
bcd var0,count_0,$deal_with_obstacle
gmw head_x,head_y,#1
b $quit_step_head
&head_dir_left
sub head_x,head_x,#1
gmw head_x,head_y,#1
sub head_x,head_x,#1
gmr var0,head_x,head_y
gmr var0,head_x,head_y
bcd var0,count_0,$deal_with_obstacle
gmw head_x,head_y,#1
b $quit_step_head
&deal_with_obstacle
bcd head_x,pomme_x, $lost
bcd head_y,pomme_y, $lost
add score,score, #4
b $pick_pomme
//quit step head
&quit_step_head
ldr var1,#1
sub count_0,tail_y,#1
gmr var0, tail_x,count_0
gmr var0, tail_x,count_0
bce var0,var1, $tail_up
add count_0,tail_x,#1
gmr var0,count_0,tail_y
gmr var0,count_0,tail_y
bce var0,var1, $tail_right
add count_0,tail_y,#1
gmr var0,tail_x,count_0
gmr var0,tail_x,count_0
bce var0,var1, $tail_down
sub count_0,tail_x,#1
gmr var0,count_0,tail_y
gmr var0,count_0,tail_y
bce var0,var1, $tail_left
&tail_up
gmw tail_x, tail_y, #0
gmw tail_x, count_0,#0
sub tail_y,tail_y,#2
b $tail_quit
&tail_right
gmw tail_x, tail_y, #0
gmw count_0, tail_y,#0
add tail_x,tail_x,#2
b $tail_quit
&tail_down
gmw tail_x,tail_y	,#0
gmw tail_x,count_0,#0
add tail_y,tail_y,#2
b $tail_quit
&tail_left
gmw tail_x, tail_y, #0
gmw count_0,tail_y,#0
sub tail_x,tail_x,#2
&tail_quit
b $snake_move
&lost
ldr count_0,#0
ldr count_1,#0
ldr count_2,#0
ldr var0,#0
ldr var1,#0
&loose_time_div
add count_0,count_0,#1
bcd count_0,count_2,$loose_time_div
nop//add count_1,count_1,#1
nop//bcd count_1,count_2,$loose_time_div
gmw var0,var1,#1
add var0,var0,#1
bcd var0,count_2,$loose_time_div
add var1,var1,#1
bcd var1,count_2,$loose_time_div
b $main
&rand
push count_0
push count_1
push count_2
ldr count_0,#0xEE
ldr count_1,#3
ldr count_2,#73
mul count_1,count_1,r0
mul r0,r0,r0
mul count_0,count_0,r0
add r0,count_1,count_2
add r0,r0,count_0
pop count_2
pop count_1
pop count_0
pop pc