790 lines
14 KiB
NASM
790 lines
14 KiB
NASM
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.equ HEAD_X, 0x1000 ; snake head's position on x-axis
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.equ HEAD_Y, 0x1004 ; snake head's position on y-axis
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.equ TAIL_X, 0x1008 ; snake tail's position on x-axis
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.equ TAIL_Y, 0x100C ; snake tail's position on y-axis
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.equ SCORE, 0x1010 ; score address
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.equ GSA, 0x1014 ; game state array
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.equ STACK, 0x2000 ; stack position
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.equ LEDS, 0x2000 ; LED addresses
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.equ SEVEN_SEGS, 0x1198 ; 7-segment display addresses
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.equ RANDOM_NUM, 0x2010 ; Random number generator address
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.equ BUTTONS, 0x2030 ; Button addresses
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#=============================
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addi sp, zero, STACK
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call wait_restart
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main_init:
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call wait
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main:
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call get_input #check for input
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call hit_test #check for collision
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add a0, zero, zero
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add t0, v0, zero
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addi t1, zero, 1
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bne v0, t1, main_no_food #if (collision != 1) -> skip
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#check for food and update score
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call create_food #create food
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ldw t2, SCORE(zero) #save current score
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addi t3, zero, 99
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addi a0, zero, 1
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beq t2, t3, main_no_food
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addi t2, t2, 1 #increment score
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stw t2, SCORE(zero) #store new score
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main_no_food:
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addi t1, zero, 2 #t2 = 2 (collision detect value)
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bne v0, t1, main_no_hit #if (v0 != 2) -> skip next instruction
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call wait_restart #else terminate game
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main_no_hit:
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call move_snake #update snake's position
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call clear_leds
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call draw_array #draw the array
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call display_score
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call wait #wait
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call restart_game #restart game
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bne v0 , zero, main_init
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br main #loop main
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#=============================
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; BEGIN:wait_restart
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wait_restart:
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call show_restart
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call wait
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call restart_game
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beq v0,zero, wait_restart
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call main_init
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;END:wait_restart
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#=============================
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; BEGIN:wait
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wait:
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addi t0, zero, 1
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slli t0, t0, 21
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addi t1, zero, 0
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wait_rec:
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addi t1, t1, 1
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blt t1, t0, wait_rec
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ret
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;END:wait
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#=============================
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;BEGIN:show_restart
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show_restart:
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stw ra, 0(sp)
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addi sp, sp, -4
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call write_r
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call write_e
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call write_s
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call write_t
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call write_a
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call write_r
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call write_t
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addi t0, zero, 12
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loop:
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call move_snake
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addi t0, t0 ,-1
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bne t0, zero, loop
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#get origin return address
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ldw ra, 0(sp)
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addi sp, sp, 4
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ret
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write_r:
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stw ra, 0(sp)
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addi sp, sp, -4
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addi a0, zero, 11
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call create_line_4
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call move_snake
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call wait
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#create point at y = 2
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addi a1, zero, 2
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call create_snake
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call move_snake
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call wait
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#skip line
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call move_snake
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call wait
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#get origin return address
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ldw ra, 0(sp)
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addi sp, sp, 4
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ret
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write_e:
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stw ra, 0(sp)
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addi sp, sp, -4
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call create_line_4
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call move_snake
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call wait
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call create_line_2
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#create point at y = 5
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addi a1, zero, 5
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call create_snake
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call move_snake
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call wait
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#skip line
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call move_snake
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call wait
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#get origin return address
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ldw ra, 0(sp)
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addi sp, sp, 4
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ret
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write_s:
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stw ra, 0(sp)
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addi sp, sp, -4
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call create_line_2
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#create point at y = 5
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addi a1, zero, 5
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call create_snake
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call move_snake
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call wait
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#create point at y = 2
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addi a1, zero, 2
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call create_snake
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#create point at y = 4
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addi a1, zero, 4
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call create_snake
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#create point at y = 5
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addi a1, zero, 5
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call create_snake
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call move_snake
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call wait
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#skip line
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call move_snake
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call wait
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#get origin return address
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ldw ra, 0(sp)
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addi sp, sp, 4
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ret
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write_t:
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stw ra, 0(sp)
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addi sp, sp, -4
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call create_line_4
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call move_snake
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call wait
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#create point at y = 3
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addi a1, zero, 3
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call create_snake
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call move_snake
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call wait
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#skip line
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call move_snake
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call wait
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#get origin return address
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ldw ra, 0(sp)
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addi sp, sp, 4
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ret
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write_a:
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stw ra, 0(sp)
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addi sp, sp, -4
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call create_line_3
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call move_snake
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call wait
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#create point at y = 2
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addi a1, zero, 2
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call create_snake
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call move_snake
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call wait
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call create_line_3
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call move_snake
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call wait
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#skip line
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call move_snake
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call wait
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#get origin return address
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ldw ra, 0(sp)
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addi sp, sp, 4
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ret
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;END:show_restart
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#=============================
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;BEGIN:create_pattern:
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#helps the show_restart procedure by creating a line pattern
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create_line_4:
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stw ra, 0(sp)
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addi sp, sp, -4
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addi a0, zero, 11
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call create_line_2
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addi a1, zero, 4
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call create_snake
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addi a1, zero, 5
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call create_snake
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#get origin return address
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ldw ra, 0(sp)
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addi sp, sp, 4
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ret
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create_line_3:
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stw ra, 0(sp)
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addi sp, sp, -4
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addi a0, zero, 11
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addi a1, zero, 3
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call create_snake
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addi a1, zero, 4
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call create_snake
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addi a1, zero, 5
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call create_snake
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#get origin return address
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ldw ra, 0(sp)
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addi sp, sp, 4
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ret
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create_line_2:
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stw ra, 0(sp)
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addi sp, sp, -4
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addi a0, zero, 11
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addi a1, zero, 2
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call create_snake
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addi a1, zero, 3
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call create_snake
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#get origin return address
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ldw ra, 0(sp)
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addi sp, sp, 4
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ret
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;END:create_pattern:
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#=============================
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;BEGIN:create_snake
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create_snake:
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#a0 = Head_x_coord, a1 = head_y_coord
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slli t0, a0, 3
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add t0, t0, a1 #t0 = 8x + y (GSA elem)
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slli t0, t0, 2 #GSA elem address
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addi t1, zero, 1 #direction = left
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stw t1, GSA(t0)
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ret
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;END:create_snake
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#=============================
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; BEGIN:clear_leds
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clear_leds:
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stw zero, LEDS (zero) #LED0 = 0
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stw zero, LEDS+4 (zero) #LED1 = 1
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stw zero, LEDS+8 (zero) #LED2 = 2
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ret
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; END:clear_leds
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#=============================
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; BEGIN: set_pixel
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set_pixel:
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#a0 = x, a1 = y
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add t1, zero, zero #comparator 1
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add t2, zero, zero #comparator 2
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add t3, zero, zero #final leds layout
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cmpgeui t1, a0, 4 # t1 = x >= 4 ? 1 : 0
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beq t1, zero, lzero # if (a0 < 4) -> lzero
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cmpgeui t2, a0, 8 # t2 = x >= 8 ? 1 : 0
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beq t2, zero, lone # elsif (x < 8) -> lone
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bne t2, zero, ltwo #else -> ltwo
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lzero:
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add t6, zero, zero #t6 = 0
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br pixelize # -> pixelize
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lone:
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addi t6, zero, 4 #t6 = 4
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br pixelize # -> pixelize
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ltwo:
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addi t6, zero, 8 #t6 = 8
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br pixelize # -> pixelize
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pixelize:
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ldw t5, LEDS(t6) #t5 = mem[t6 + LEDS]
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sub t4, a0, t6 #t4 = x - t6
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slli t4, t4, 3 #t4 << 3
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add t4, t4, a1 #t4 += y
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addi t3, zero, 1 #t3 = 1
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sll t3, t3, t4 #t3 << t4
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or t3, t3, t5 #t3 |= t5
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stw t3, LEDS(t6) #mem[LEDS + t6] = t3
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ret #return
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; END: set_pixel
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#=============================
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; BEGIN:get_input
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get_input:
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addi t1, zero, 1 #mask
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ldw t2, BUTTONS+4(zero) #edgecapture states
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stw zero, BUTTONS+4(zero)
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ldw t3, HEAD_X(zero) #head x coord
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ldw t4, HEAD_Y(zero) #head y coord
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slli t3, t3, 3 #head_x << 3
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add t4, t3, t4 #t4 = 8x + y (GSA element address)
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slli t4, t4, 2
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ldw t7, GSA(t4) #t7 = GSAheadval
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and t5, t1, t2 #t5 = edgecapture & 1
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addi t3, zero, 4 #t3 = 4 (impossible value)
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beq t7, t3, 4 #if t7 == t3 -> skip next instruction
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bne t5, zero, left #if(edgecapture & 1 !=0) -> left
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slli t1, t1, 1 #t1 << 1
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and t5, t1, t2 #t5 = edgecapture & 10
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addi t3, zero, 3 #t3 = 3 (impossible value)
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beq t7, t3, 4 #if t7 == t3 -> skip next instruction
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bne t5, zero, up #if(edgecapture & 10 !=0) -> up
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slli t1, t1, 1 #t1 << 1
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and t5, t1, t2 #t5 = edgecapture & 100
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addi t3, zero, 2 #t3 = 2 (imopossible val)
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beq t7, t3, 4 #if t7 == t3 -> skip next instruction
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bne t5, zero, down #if(edgecapture & 100 !=0) -> down
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||
|
|
slli t1, t1, 1 #t1 << 1
|
||
|
|
and t5, t1, t2 #t5 = edgecapture & 1000
|
||
|
|
addi t3, zero, 1 #t3 = 1 (impossible value)
|
||
|
|
beq t7, t3, 4 #if t7 == t3 -->skip next instruction
|
||
|
|
bne t5, zero, right #if(edgecapture & 1000 !=0) -> right
|
||
|
|
|
||
|
|
ret
|
||
|
|
|
||
|
|
left:
|
||
|
|
addi t6, zero, 1 #t6 = 1
|
||
|
|
stw t6, GSA(t4) #mem[GSA + t4] = 1
|
||
|
|
|
||
|
|
ret
|
||
|
|
up:
|
||
|
|
addi t6, zero, 2 #t6 = 1
|
||
|
|
stw t6, GSA(t4) #mem[GSA + t4] = 2
|
||
|
|
|
||
|
|
ret
|
||
|
|
|
||
|
|
down:
|
||
|
|
addi t6, zero, 3 #t6 = 3
|
||
|
|
stw t6, GSA(t4) #mem[GSA + t4] = 3
|
||
|
|
|
||
|
|
ret
|
||
|
|
|
||
|
|
right:
|
||
|
|
addi t6, zero, 4 #t6 = 4
|
||
|
|
stw t6, GSA(t4) #mem[GSA + t4] = 4
|
||
|
|
|
||
|
|
ret
|
||
|
|
|
||
|
|
; END:get_input
|
||
|
|
|
||
|
|
|
||
|
|
#=============================
|
||
|
|
|
||
|
|
; BEGIN:move_snake
|
||
|
|
move_snake:
|
||
|
|
#a0 = foodEaten ? 1 : 0
|
||
|
|
ldw t0, HEAD_X(zero) #t0: head x coord
|
||
|
|
ldw t1, HEAD_Y(zero) #t1: head y coord
|
||
|
|
slli t2, t0, 3 #x = 8x
|
||
|
|
add t2, t2, t1 #t2 = 8x + y (Head GSA element address)
|
||
|
|
slli t2, t2, 2
|
||
|
|
ldw t5, GSA(t2) #t2: Head direction vector
|
||
|
|
|
||
|
|
head:
|
||
|
|
addi t6, zero, 1 #t6: current direction
|
||
|
|
bne t5, t6, not_left #if(HeadVect == 1) -> go_left
|
||
|
|
addi t0, t0, -1
|
||
|
|
br check_head
|
||
|
|
|
||
|
|
not_left:
|
||
|
|
addi t6, zero, 2
|
||
|
|
bne t5, t6, not_up #if(HeadVect == 2) -> go_up
|
||
|
|
addi t1, t1, -1
|
||
|
|
br check_head
|
||
|
|
|
||
|
|
not_up:
|
||
|
|
addi t6, zero, 3
|
||
|
|
bne t5, t6, not_down #if(HeadVect == 3) -> go_down
|
||
|
|
addi t1, t1, 1
|
||
|
|
br check_head
|
||
|
|
|
||
|
|
not_down:
|
||
|
|
addi t6, zero, 4
|
||
|
|
bne t5, t6, not_right #if(HeadVect == 4) -> go_right
|
||
|
|
addi t0, t0, 1
|
||
|
|
br check_head
|
||
|
|
|
||
|
|
not_right: # NO movements to make !
|
||
|
|
ret
|
||
|
|
|
||
|
|
check_head:
|
||
|
|
slli t2, t0, 3
|
||
|
|
add t2, t2, t1
|
||
|
|
slli t2, t2, 2
|
||
|
|
stw t5, GSA(t2)
|
||
|
|
stw t0, HEAD_X(zero)
|
||
|
|
stw t1, HEAD_Y(zero)
|
||
|
|
|
||
|
|
beq a0, zero, no_fud
|
||
|
|
br fud
|
||
|
|
|
||
|
|
no_fud:
|
||
|
|
ldw t3, TAIL_X(zero) #t3: tail x coord
|
||
|
|
ldw t4, TAIL_Y(zero) #t4: tail y coord
|
||
|
|
slli t2, t3, 3 #x = 8x
|
||
|
|
add t2, t2, t4 #t5 = 8x + y (Tail GSA element address)
|
||
|
|
slli t2, t2, 2
|
||
|
|
ldw t5, GSA(t2) #t5: Tail direction vector
|
||
|
|
|
||
|
|
addi t6, zero, 1 #t6: current direction
|
||
|
|
bne t5, t6, tail_not_left #if(TailVect != 1) -> go_left
|
||
|
|
addi t3, t3, -1
|
||
|
|
br pre_fud
|
||
|
|
|
||
|
|
tail_not_left:
|
||
|
|
addi t6, zero, 2
|
||
|
|
bne t5, t6, tail_not_up #if(TailVect == 2) -> go_up
|
||
|
|
addi t4, t4, -1
|
||
|
|
br pre_fud
|
||
|
|
|
||
|
|
tail_not_up:
|
||
|
|
addi t6, zero, 3
|
||
|
|
bne t5, t6, tail_not_down #if(TailVect == 3) -> go_down
|
||
|
|
addi t4, t4, 1
|
||
|
|
br pre_fud
|
||
|
|
|
||
|
|
tail_not_down:
|
||
|
|
addi t6, zero, 4
|
||
|
|
bne t5, t6, pre_fud #if(TailVect == 4) -> go_right
|
||
|
|
addi t3, t3, 1
|
||
|
|
br pre_fud
|
||
|
|
|
||
|
|
pre_fud:
|
||
|
|
stw zero, GSA(t2)
|
||
|
|
|
||
|
|
stw t3, TAIL_X(zero)
|
||
|
|
stw t4, TAIL_Y(zero)
|
||
|
|
|
||
|
|
fud:
|
||
|
|
ret
|
||
|
|
|
||
|
|
; END:move_snake
|
||
|
|
|
||
|
|
#=============================
|
||
|
|
|
||
|
|
; BEGIN:draw_array
|
||
|
|
draw_array:
|
||
|
|
addi sp, sp, -4
|
||
|
|
stw ra, 0 (sp)
|
||
|
|
|
||
|
|
addi t0, zero, GSA
|
||
|
|
|
||
|
|
add t1, zero, zero #y
|
||
|
|
add t2, zero, zero #x
|
||
|
|
|
||
|
|
addi t4, zero , 8 #8
|
||
|
|
addi t5, zero , 12 #12
|
||
|
|
|
||
|
|
draw_array_i:
|
||
|
|
ldw t3, 0 (t0) #GSAi_val
|
||
|
|
|
||
|
|
beq t3,zero, incr_y #Do not Draw
|
||
|
|
|
||
|
|
add a0, t2, zero
|
||
|
|
add a1, t1, zero
|
||
|
|
|
||
|
|
# PREPARE FUNCTION CALL
|
||
|
|
|
||
|
|
addi sp, sp, -12
|
||
|
|
stw t0, 0 (sp)
|
||
|
|
stw t1, 4 (sp)
|
||
|
|
stw t2, 8 (sp)
|
||
|
|
|
||
|
|
call set_pixel # SET PIXEL
|
||
|
|
|
||
|
|
ldw t0, 0 (sp)
|
||
|
|
ldw t1, 4 (sp)
|
||
|
|
ldw t2, 8 (sp)
|
||
|
|
addi sp, sp, 12
|
||
|
|
|
||
|
|
# UNDO FUNCTION CALL
|
||
|
|
|
||
|
|
addi t4, zero , 8 #8
|
||
|
|
addi t5, zero , 12 #12
|
||
|
|
|
||
|
|
incr_y:
|
||
|
|
addi t1, t1, 1
|
||
|
|
addi t0, t0, 4
|
||
|
|
blt t1, t4, draw_array_i;
|
||
|
|
|
||
|
|
addi t2, t2, 1
|
||
|
|
add t1, zero, zero
|
||
|
|
blt t2, t5, draw_array_i;
|
||
|
|
|
||
|
|
ldw ra, 0 (sp)
|
||
|
|
addi sp, sp, 4
|
||
|
|
ret
|
||
|
|
; END:draw_array
|
||
|
|
|
||
|
|
#=============================
|
||
|
|
|
||
|
|
; BEGIN:create_food
|
||
|
|
create_food:
|
||
|
|
addi t1, zero, 255 # mask lowest byte
|
||
|
|
addi t2, zero, 384 # max val mem
|
||
|
|
addi t4, zero, 5 #value of food in GSA
|
||
|
|
|
||
|
|
random_food:
|
||
|
|
ldw t0, RANDOM_NUM (zero) # read random
|
||
|
|
and t0,t0,t1 # lowest byte of random
|
||
|
|
slli t0, t0, 2
|
||
|
|
bge t0, t2, random_food
|
||
|
|
ldw t3, GSA (t0)
|
||
|
|
bne t3, zero, random_food #checks if cell is empty
|
||
|
|
|
||
|
|
stw t4, GSA (t0) #add food
|
||
|
|
|
||
|
|
ret
|
||
|
|
; END:create_food
|
||
|
|
|
||
|
|
#=============================
|
||
|
|
|
||
|
|
; BEGIN:hit_test
|
||
|
|
hit_test:
|
||
|
|
#Collide with food
|
||
|
|
ldw t0, HEAD_X(zero) #head_x_coord
|
||
|
|
ldw t1, HEAD_Y(zero) #head_y_coord
|
||
|
|
|
||
|
|
slli t2, t0, 3 #t2 = 8x
|
||
|
|
add t2, t2, t1 #t2 = 8x + y (GSA elem address)
|
||
|
|
slli t2, t2, 2
|
||
|
|
ldw t3, GSA(t2) #value of the GSA elem at head coord
|
||
|
|
|
||
|
|
addi t7, zero, 1 #t6: current direction
|
||
|
|
bne t3, t7, check_not_left #if(TailVect != 1) -> go_left
|
||
|
|
addi t0, t0, -1
|
||
|
|
br check_cell
|
||
|
|
|
||
|
|
check_not_left:
|
||
|
|
addi t7, zero, 2
|
||
|
|
bne t3, t7, check_not_up #if(TailVect != 2) -> go_up
|
||
|
|
addi t1, t1, -1
|
||
|
|
br check_cell
|
||
|
|
|
||
|
|
check_not_up:
|
||
|
|
addi t7, zero, 3
|
||
|
|
bne t3, t7, check_not_down #if(TailVect != 3) -> go_down
|
||
|
|
addi t1, t1, 1
|
||
|
|
br check_cell
|
||
|
|
|
||
|
|
check_not_down:
|
||
|
|
addi t7, zero, 4
|
||
|
|
bne t3, t7, check_cell #if(TailVect != 4) -> exit
|
||
|
|
addi t0, t0, 1
|
||
|
|
|
||
|
|
|
||
|
|
check_cell:
|
||
|
|
|
||
|
|
addi t6, zero, 11
|
||
|
|
bltu t6, t0, hit_edge
|
||
|
|
addi t6, zero, 7
|
||
|
|
bltu t6, t1, hit_edge
|
||
|
|
|
||
|
|
slli t2, t0, 3 #t2 = 8x
|
||
|
|
add t2, t2, t1 #t2 = 8x + y (GSA elem address)
|
||
|
|
slli t2, t2, 2
|
||
|
|
|
||
|
|
ldw t3, GSA(t2) #value of the GSA elem after head coord
|
||
|
|
|
||
|
|
beq t3, zero, no_hit
|
||
|
|
|
||
|
|
addi t4, zero, 5 #food value
|
||
|
|
beq t3, t4, hit_food
|
||
|
|
bltu t3, t4, hit_edge
|
||
|
|
|
||
|
|
hit_edge:
|
||
|
|
addi v0, zero, 2
|
||
|
|
ret
|
||
|
|
|
||
|
|
hit_food:
|
||
|
|
addi v0, zero, 1 #food is eaten since headGSAval = 5
|
||
|
|
ret #else return v0
|
||
|
|
|
||
|
|
no_hit:
|
||
|
|
add v0, zero, zero #v0 = 0
|
||
|
|
ret #return v0
|
||
|
|
|
||
|
|
; END:hit_test
|
||
|
|
|
||
|
|
#=============================
|
||
|
|
|
||
|
|
; BEGIN:display_score
|
||
|
|
display_score:
|
||
|
|
ldw t1, SCORE (zero) #Value of score
|
||
|
|
|
||
|
|
add t2, zero, zero # 10 units
|
||
|
|
addi t3, zero, 10 #min to substract
|
||
|
|
|
||
|
|
bin_to_dec:
|
||
|
|
blt t1, t3, draw_score # t1 < 10 -> go draw
|
||
|
|
sub t1, t1, t3 # t1 = t1 - 10;
|
||
|
|
addi t2, t2, 1 # t2 = t2 + 1 ;
|
||
|
|
br bin_to_dec
|
||
|
|
draw_score:
|
||
|
|
|
||
|
|
ldw t6, font_data (zero)
|
||
|
|
stw t6, SEVEN_SEGS+0 (zero)
|
||
|
|
stw t6, SEVEN_SEGS+4 (zero)
|
||
|
|
|
||
|
|
slli t2, t2, 2
|
||
|
|
ldw t6, font_data (t2)
|
||
|
|
stw t6, SEVEN_SEGS+8 (zero)
|
||
|
|
|
||
|
|
slli t1, t1, 2
|
||
|
|
ldw t6, font_data (t1)
|
||
|
|
stw t6, SEVEN_SEGS+12 (zero)
|
||
|
|
|
||
|
|
ret
|
||
|
|
|
||
|
|
; END:display_score
|
||
|
|
|
||
|
|
#=============================
|
||
|
|
|
||
|
|
; BEGIN:restart_game
|
||
|
|
restart_game:
|
||
|
|
ldw t5, BUTTONS+4(zero) #EDGE
|
||
|
|
addi t7, zero, 0b010000
|
||
|
|
and t6, t5, t7 #010000 & t1
|
||
|
|
beq t6, zero, exit_no_restart
|
||
|
|
stw zero, BUTTONS+4(zero)
|
||
|
|
|
||
|
|
#reset_mem:
|
||
|
|
stw zero, HEAD_Y (zero)
|
||
|
|
stw zero, HEAD_X (zero)
|
||
|
|
stw zero, TAIL_Y (zero)
|
||
|
|
stw zero, TAIL_X (zero)
|
||
|
|
stw zero, SCORE (zero)
|
||
|
|
|
||
|
|
add t2, zero, zero
|
||
|
|
addi t3, zero, 384
|
||
|
|
reset_gsa:
|
||
|
|
stw zero, GSA(t2)
|
||
|
|
addi t2, t2, 4
|
||
|
|
blt t2, t3, reset_gsa
|
||
|
|
|
||
|
|
#init_gsa:
|
||
|
|
addi t4 , zero, 4
|
||
|
|
stw t4, GSA (zero)
|
||
|
|
|
||
|
|
|
||
|
|
addi sp, sp, -4
|
||
|
|
stw ra, 0 (sp)
|
||
|
|
call clear_leds
|
||
|
|
call create_food
|
||
|
|
call draw_array
|
||
|
|
call display_score
|
||
|
|
ldw ra, 0 (sp)
|
||
|
|
addi sp, sp, 4
|
||
|
|
|
||
|
|
addi v0, zero, 1
|
||
|
|
br exit_restart_func
|
||
|
|
exit_no_restart:
|
||
|
|
addi v0, zero, 0
|
||
|
|
exit_restart_func:
|
||
|
|
ret
|
||
|
|
; END:restart_game
|
||
|
|
|
||
|
|
#=============================
|
||
|
|
|
||
|
|
font_data:
|
||
|
|
.word 0xFC ; 0
|
||
|
|
.word 0x60 ; 1
|
||
|
|
.word 0xDA ; 2
|
||
|
|
.word 0xF2 ; 3
|
||
|
|
.word 0x66 ; 4
|
||
|
|
.word 0xB6 ; 5
|
||
|
|
.word 0xBE ; 6
|
||
|
|
.word 0xE0 ; 7
|
||
|
|
.word 0xFE ; 8
|
||
|
|
.word 0xF6 ; 9
|
||
|
|
|
||
|
|
|
||
|
|
end:
|