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@LucasLarson
Created March 27, 2019 03:43
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MIPS MARS blue-on-yellow bitmap
#-------------------\
# |
# MIPS MARS Bitmap |
# |
# Lucas Larson |
# 2019-03-26 |
# |
# # # # # # # # # # /
.data
frameBuffer:
.space 0x80000 # (512 × 256)₁₆ pixels
n:
.word 15 # n = 2⁴ - 1
m:
.word 31 # m = 2⁵ - 1
.text
drawLine:
la $t1, frameBuffer
color:
li $t3, 0x00FFFF00 # $t3 ← 0x00RRGGbb yellow
li $t4, 0x000000FF # $t4 ← 0x00rrggBB blue
count:
li $t6, 131072 # $t6 = 512 × 256
li $t9, 0 # $t9, $t2, and $t5 ← 0
li $t2, 0 # $t9, $t2, and $t5 ← 0
li $t5, 0 # $t9, $t2, and $t5 ← 0
yellow:
sw $t3, 0 ($t1) # fill square
addi $t1, $t1, 4 # increment address by 4
addi $t9, $t9, 1 # $t9++
beq $t9, $t6, reset # if $t9 == 512 × 256 goto reset
j yellow # else goto yellow
reset:
subi $t1, $t1, 4 # go to previous address
subi $t9, $t9, 1 # $t9--
beq $t9, 0, crux # if $t9 == 0 goto crux
j reset # else goto reset
loop:
subi $t1, $t1, 512 # subtract amount wanted
addi $t1, $t1, 2048 # go to next row
addi $t9, $zero, 0
addi $t2, $t2, 1 # $t2++
beq $t2, 128, exit # if $t2 == distance goto exit
j box # else goto box
crux:
edge:
addi $t1, $t1, 2048 # row + 512 × 4
addi $t5, $t5, 1 # $t3++
beq $t5, 64, box # if $t9 == 2⁶ goto box
j edge # else goto edge
box:
sw $t4, 768 ($t1) # 768 = (2⁵ × 2⁵ + 2⁵ × 2⁴) / 2
addi $t1, $t1, 4 # increment address
addi $t9, $t9, 1 # address increment check
beq $t9, 128, loop # if $t9 == 2⁷ goto loop
j box # else goto box
exit:
li $v0, 10 # exit code
syscall:
syscall
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