Java to Assembly - Page 5

Question

wildgoose 420 Practically a Posting Shark

14 Years Ago

Since this is no longer a school project I went in and cleaned top to bottom. You need to finish at bottom where indicated.
Review each section of code and understand how it works!

.data # variable declarations follow this line
iSAFE: 1
iCHASM: 2
iTRAP: 3
iDESTINATION: 4

maze: .space 144 # 9x9 stored in a 16x9 buffer 
robot_x: .word 0
robot_y: .word 0
robot_m_x: .word 0
robot_m_y: .word 0
robot_state: .word 0
robot_instructions: .space 64

# Robot State Message Table
MsgRobotTbl:		
		.word		MsgRS1
		.word		MsgRS2
		.word		MsgRS3
		.word		MsgRS4
		.word		MsgRS5
MsgFailsDestination: .asciiz "Robot fails to reach Destination\n"

MsgRS1: .asciiz "Robot is at a safe place\n" 
MsgRS2: .asciiz "Robot falls into Chasm\n"
MsgRS3: .asciiz "Robot falls into the trap\n"
MsgRS4: .asciiz "Robot reaches Destination\n"
MsgRS5: .asciiz "Robot fails to reach Destination\n"
MsgFinal:	.asciiz "Robot final location X: "
MsgY:		.asciiz " Y: "
MsgCR:		.asciiz "\n"
MsgRobotState:  .asciiz  "Robot State: \n"
MsgFallenChasm:  .asciiz  "Robot has fallen into a chasm\n"
MsgFallenTrap:   .asciiz  "Robot has fallen into a trap\n"
MsgReachedDestination:  .asciiz  "Robot has reached Destination\n"
MsgSafePlace:    .asciiz  "Robot is at a safe place\n"
MsgFallsChasm:	.asciiz   "Robot falls into Chasm\n"
MsgFallsTrap:   .asciiz   "Robot falls into the trap\n"
MsgReachesDestination: .asciiz "Robot reaches Destination\n"

.text # CODE SECTION OF ASM FILE

#main:
	li $v0,30 			# Get time
	syscall 			# CMD: Get Time
		# $a0 = lower 32-bits, $a1=upper 32-bits

		# Seed RNG (Random Number Generator)
	move $a1,$a0 		# get lower 32-bit time as seed
	li $a0,0 			# Rng#0
	syscall 			# CMD: Seed the RNG

		# Clear Entire Maze Array

	la $t0, maze 		# address of maze
	li $t3, 0              
	li $t1, 144

clr: 					# repeat if not finished yet.
	sb $t3, 0($t0) 
	add $t0, $t0, 1 	# address++
	add $t1, $t1, -1 	# count--
	bgtz $t1, clr

		# _______________
		# Setup variables

	la $t0, maze # base address

	li $t1,1 			# iSAFE: 
	sb $t1, 0x11($t0) 	# maze[1][1] = 1;

	li $t1,2 			# iCHASM:
	sb $t1, 0x12($t0) 	# maze[1][2] = 2    
	sb $t1, 0x24($t0) 	# maze[2][4] = 2

	li $t1, 3 			#iTRAP: 
	sb $t1, 0x23($t0) 	# maze[2][3] = 3
	sb $t1, 0x34($t0) 	# maze[3][4] = 3

	li $t1, 4 			#iDESTINATION: 
	sb $t1, 0x32($t0)	# maze[3][2] = 4;

		# robot_x = 1
	la $t0,robot_x
	li $t1,1
	sw $t1,0($t0)

		# robot_y = 2
	la $t0,robot_y
	li $t1,2
	sw $t1,0($t0)

		# init robot_state = 5
	la $t0,robot_state
	li $t1,5
	sw $t1,0($t0)

	la	$t7,robot_instructions		# index
	li	$t6,64			# Num of loops

		# _______________
		# TOP of BIG Loop
MoveLoop:

		# Get a Random #
	li $a0, 0 			# Rng#
	li $a1, 4 			# rand() %4 {0...3}
	li $v0, 42
	syscall 			# Get RNG
		# $a0 = {0...3}
	add $a0, $a0, 1 	# {1...4}

		# Store Robot instruction
	sb	$a0,0($t7)		# robot_instructions[i] = rnd{ 1...4 }
	add $t7, $t7, 1		# increment address

	add	$a0, $a0, -1
	bgtz $a0,	RJump

		# ____________
		# case 1: MOVE

	la $t1,robot_m_x
	la $t0,robot_x

	lw	$t2,0($t1)
	sw	$t2,0($t0)		# robot_x = robot_m_x

	la	$t1,robot_m_y
	la	$t0,robot_y
	lw	$t2,0($t1)
	add	$t2,$t2,1
	sw	$t2,0($t0)		# robot_y = robot_m_y + 1

	j	Processing		# Goto Processing

	
RJump:
	add	$a0, $a0, -1
	bgtz $a0,	 RLeft

		# ____________
		# case 2: Jump

	la $t1,robot_m_x
	la $t0,robot_x

	lw	$t2,0($t1)
	sw	$t2,0($t0)		# robot_x = robot_m_x

	la	$t1,robot_m_y
	la	$t0,robot_y
	lw	$t2, 0($t1)
	add	$t2, $t2, 2
	sw	$t2, 0($t0)		# robot_y = robot_m_y + 2

	j	Processing		# Goto Processing


RLeft:
	add	$a0, $a0, -1
	bgtz $a0,	RRight

		# ____________
		# case 3: Left

	la $t1,robot_m_x
	la $t0,robot_x
	lw	$t2,0($t1)
	add	$t2, $t2, -1
	sw	$t2,0($t0)		# robot_x = robot_m_x - 1


	j	Processing		# Goto Processing

		# _____________
		# case 4: Right
RRight:

	la $t1,robot_m_x
	la $t0,robot_x
	lw	$t2,0($t1)
	add	$t2, $t2, 1
	sw	$t2,0($t0)		# robot_x = robot_m_x + 1

	#	______________________________
	#	Processing new robot positions!

Processing:
		#	System.out.println("Robot final location X: " + robot_x + " Y: " + robot_y);

	la $a0, MsgFinal
	li $v0, 4 	  		# specify Print String service
	syscall 			# print ASCIIz

	la $t0,robot_x
	lw $a0,0($t0)
	li $v0, 1
	syscall 			# CMD: print robot_x integer

	la $a0, MsgY
	li $v0, 4 		   	# specify Print String service
	syscall 			# print ASCIIz

	la $t0,robot_y
	lw $a0,0($t0)
	li $v0, 1
	syscall 			# CMD: print robot_Y integer

	la $a0, MsgCR
	li $v0, 4 			# specify Print String service
	syscall 			# print CRLF

		#	System.out.println ("Robot State: ");
	la $t0,robot_x
	lw $t0,0($t0)		# $t0 = robot_x
	la $t5,robot_y
	lw $t5,0($t5)		# $t5 = robot_y

		# Using $t1 ... $t4 since they look similar to 1...4
	li  $t1,1
	li  $t2,2
	li  $t3,3
	li  $t4,4

		# _____________________________________________________________________________________
		# Ref:  if (( (robot_x == 1) && (robot_y == 2)) || ( (robot_x == 2) && (robot_y == 4)) )

	bne $t0,$t1,LineA3	# jump if robot_x <> 1
	beq $t5,$t2,LineAOK	# jump if robot_y == 2	* Success *

LineA3:			# || ( (robot_x == 2) && (robot_y == 4)) )
	bne $t0,$t2, LineB	#jump if robot_x <> 2
	bne $t5,$t4, LineB	#jump if robot_y <> 4

LineAOK:   # SUCCESS

	la $a0, MsgFallenChasm
	li $v0, 4			# specify Print String service
	syscall 			# print ASCIIz
  
    la $a0, robot_state
	sw $t2,0($a0)		# robot_state = 2

		#	Process new robot positions

	j	Done


MoveHop:  j MoveLoop	# HOP to top of loop

		# ____________________________________________________________________________________
		# Ref: else if(( (robot_x == 2) && (robot_y == 3)) || ((robot_x == 3) && (robot_y == 4))) 

LineB:
	bne $t0,$t2,LineB3	# jump if robot_x <> 2 
	beq $t5,$t3,LineBOK	# jump if robot_y == 3  * Success *

LineB3: 	# || ( (robot_x == 2) && (robot_y == 4)) ) 

	bne $t0,$t3, LineC	#jump if robot_x <> 3
	bne $t5,$t4, LineC	#jump if robot_y <> 4

LineBOK:	# SUCCESS

	la $a0, MsgFallenTrap
	li $vo, 4
	syscal				#print heading

	la $a0, robot_state
	sw $t3, 0 ($a0)		#robot_state=3

	j Done


		# ___________________________________________
		# Ref:  if ((robot_x == 3) && (robot_y == 2))
LineC:
	bne $t0,$t3, LineD	# jump if robot_x <> 3
	bne $t5,$t2, LineD	# jump if robot_y <> 2

		# SUCCESS

	la $a0, MsgReachedDestination
	li $vo, 4
	syscal				#print ASCIIz

	la $a0, robot_state
	sw $t4, 0 ($a0)		#robot_state=4

	j Done

		# _________________________________________
LineD:

	la $a0, MsgSafePlace
	li $v0, 4 			# specify Print String service
	syscall				# print ASCIIz
  
	la $a0, robot_state
	sw $t4,0($a0)		# robot_state = 1

		# ___________________
		#	Print Robot State
Done:
	la	$a0, robot_state
	lw	$t0,0($a0)		# to is robot_state



### <---   Insert 4 case robot_state printing!



		# ________
		# End Loop

	add $t6, $t6, -1 	# count--
	bgtz $t1, MoveHop	# Hop back to top of big loop


	jr $ra # return

Salem commented: Phew!, what a marathon thread!, that's dedication. +36

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wildgoose 420 Practically a Posting Shark · Answer 1 · 2009-08-15T06:36:57+00:00

Also go to the top of the file. In the strings
MsyCR should be MsgCR

They should all be Msg____ <--- suffix

wildgoose 420 Practically a Posting Shark · Answer 2 · 2009-08-15T06:38:06+00:00

robot_state is an easy one!

It's in your Java code but you didn't define it here in your data!

robot_state: .word 0

malugirl4 0 Junior Poster in Training · Answer 3 · 2009-08-15T06:44:44+00:00

Yeah I just found some other simple errors in the code I just fixed cause of typos.

Is this what I should change to MsgCR I changed the top one from msycr?
Error in Assembly2 line 203 position 10: Symbol "MsgCR" not found in symbol table.
Assemble: operation completed with errors.

wildgoose 420 Practically a Posting Shark · Answer 4 · 2009-08-15T06:45:21+00:00

When you get a chance drop this in

MsgFailsDestination: .asciiz "Robot fails to reach Destination\n"
!!! Right below this line! at the top of file

# Robot State Message Table
MsgRobotTbl:		.word	MsgRS1
		.word		MsgRS2
		.word		MsgRS3
		.word		MsgRS4
		.word		MsgRS5

it's a string table

malugirl4 0 Junior Poster in Training · Answer 5 · 2009-08-15T06:46:39+00:00

I think its fixed now that I changed the msyCr

Error in Assembly2 line 227 position 15: Symbol "$LineB" not found in symbol table.
Assemble: operation completed with errors.

malugirl4 0 Junior Poster in Training · Answer 6 · 2009-08-15T06:49:13+00:00

Error in Assembly2 line 38 position 1: label "MsgFailsDestination" already defined
Assemble: operation completed with errors.

wildgoose 420 Practically a Posting Shark · Answer 7 · 2009-08-15T06:53:03+00:00

Delete the last one! There's two sitting there!

the $LineB thing. Remove the $ on both of them. They're sitting side by side.

malugirl4 0 Junior Poster in Training · Answer 8 · 2009-08-15T06:53:39+00:00

I fied the msgfailsdestination..i had it declared before

malugirl4 0 Junior Poster in Training · Answer 9 · 2009-08-15T06:56:47+00:00

Error in Assembly2 line 246: Jump target word address beyond 26-bit range
Assemble: operation completed with errors.

wildgoose 420 Practically a Posting Shark · Answer 10 · 2009-08-15T07:03:24+00:00

Codes getting pretty long!

Change at the bottom of the file

#jgz  MoveLoop	# Loop 63 times for 64 iterations.
jgz  MoveHop	# Loop 63 times for 64 iterations.

Code is trying to jump too far!

So now we need to hop a bit

#	Process new robot positiions!   <-- fix spelling

	j	PrtOut

MoveHop:  j MoveLoop

PrtOut:            <-- Find this, and modify code above this line
                             to look like this

Essentially we need a double jump since one jump is too far.
We'll jump in the middle of the program at a safe place, then jump again!

Strange, doesn't seem like the code is THAT big!
]

malugirl4 0 Junior Poster in Training · Answer 11 · 2009-08-15T07:35:23+00:00

bottom of file:

#	Process new robot posit5ions!

PrtOut:
		#	System.out.println("Robot final location X: " + robot_x + " Y: " + robot_y);

	la $a0, MsgFinal
	li $v0, 4 				# specify Print String service
	syscall # print heading

	la $t0,robot_x
	lw $a0,0($t0)
	li $v0, 1
	syscall # CMD: print robot x integer

	la $a0, MsgY
	li $v0, 4 				# specify Print String service
	syscall # print heading

	la $t0,robot_y
	lw $a0,0($t0)
	li $v0, 1
	syscall # CMD: print robot Y integer

	la $a0, MsgCR
	li $v0, 4 				# specify Print String service
	syscall # print heading

		#	System.out.println ("Robot State: ");
la $t0,robot_x
  lw $t0,0($t0)           # $t0 = robot_x
  la $t5,robot_y
#  lw $t5,0($t1)           # $t5 = robot_y
  lw $t5,0($t5)           # $t5 = robot_y

# Using $t1 ... $t4 since they look similar to 1...4
  li  $t1,1
  li  $t2,2
  li  $t3,3
  li  $t4,4

  #  register to register compares
  # Ref:  if (( (robot_x == 1) && (robot_y == 2)) || ( (robot_x == 2) && (robot_y == 4)) )
  bne $t0,$t1,LineA3   # jump if robot_x <> 1
#  beq $t5,$t2,LineA3   # jump if robot_y == 2
  beq $t5,$t2,LineAOK   # jump if robot_y == 2

LineA3:                                              # || ( (robot_x == 2) && (robot_y == 4)) )
  bne $t0,$t2, LineB    #jump if robot_x <> 2
  bne $t5,$t4, LineB    #jump if robot_y <> 4

LineAOK:   # SUCCESS

  la $a0, MsgFallenChasm
  li $v0, 4 				# specify Print String service
  syscall # print heading
  
    la $a0, robot_state
  sw $t2,0($a0)                          # robot_state = 2
#jgz  MoveLoop	# Loop 63 times for 64 iterations.
jgz  MoveHop	# Loop 63 times for 64 iterations.


	#	Process new robot positions

	j	PrtOut

MoveHop:  j MoveLoop

PrtOut:            
                      

# Process new robot positiions! <-- fix spelling j PrtOut MoveHop: j MoveLoop PrtOut: <-- Find this, and modify code above this line to look like this






Done:

  # Next conditional line
  # Ref: else if(( (robot_x == 2) && (robot_y == 3)) || ((robot_x == 3) && (robot_y == 4)))
LineB:

    add $t7, $t7, 4
	add $t6, $t6, -1
	bgtz $a0, MoveLoop		# Loop 64 times


	jr $ra # return

malugirl4 0 Junior Poster in Training · Answer 12 · 2009-08-15T07:36:44+00:00

Error in Assembly2 line 244 position 1: "jgz" directive cannot appear in text segment
Error in Assembly2 line 253 position 1: label "PrtOut" already defined
Assemble: operation completed with errors.

wildgoose 420 Practically a Posting Shark · Answer 13 · 2009-08-15T07:43:30+00:00

Yep
#jgz MoveLoop # Loop 63 times for 64 iterations.
jgz MoveHop # Loop 63 times for 64 iterations.
Should be removed!

That second PrtOut:
should be removed!
MoveHop: j MoveLoop

PrtOut: <--- Delete this line

Any code that has the # in front of is commented out code and should be eventualy removed!

wildgoose 420 Practically a Posting Shark · Answer 14 · 2009-08-15T07:47:28+00:00

Once you get a clean assemble, compare the following code.
It should look like this!

# ______________________________
  #  register to register compares
  # Ref:  if (( (robot_x == 1) && (robot_y == 2)) || ( (robot_x == 2) && (robot_y == 4)) )
  bne $t0,$t1,LineA3   # jump if robot_x <> 1
  beq $t5,$t2,LineAOK  # jump if robot_y == 2

LineA3:                                              # || ( (robot_x == 2) && (robot_y == 4)) )
  bne $t0,$t2,LineB    #jump if robot_x <> 2
  bne $t5,$t4,LineB    #jump if robot_y <> 4

LineAOK:   # SUCCESS

  la $a0, MsgFallenChasm
  li $v0, 4 				# specify Print String service
  syscall # print heading
  
  la $a0, robot_state
  sw $t2,0($a0)                          # robot_state = 2

  j  Done


  # ______________________________
  # Next conditional line
  # Ref: else if(( (robot_x == 2) && (robot_y == 3)) || ((robot_x == 3) && (robot_y == 4)))
LineB:


   j Done

Line C:


 j Done

Line D:


 j Done


Done:

Note the Java comment in Line A and how each condition was handled.
It will be up to you to try to recreate the Line B version
Line C, and Line D versions!

Each Line# is a conditional line that was in your Java.

Everything you need is there! Just examine how Line A code block works.

malugirl4 0 Junior Poster in Training · Answer 15 · 2009-08-15T07:50:30+00:00

ok it compiled. but it doesn't print anything it keeps going through line 60-65

malugirl4 0 Junior Poster in Training · Answer 16 · 2009-08-15T07:52:55+00:00

malugirl4 0 Junior Poster in Training

14 Years Ago

ok i'm doing b, c, d now

wildgoose 420 Practically a Posting Shark · Answer 17 · 2009-08-15T08:00:48+00:00

Hmm!

# Clear Entire Maze Array

la $t0, maze # load address of maze
li $t3, 2               # <-- Fill maze with (2)
li $t1, 144

clr: # repeat if not finished yet.
#	la $t0, maze # base address    <---- DELETE THIS LINE!
 It keeps resetting the pointer back to the base!
####	li $t3, 2 		# maze[i] = 2   <-- this one too!
	sb $t3, 0($t0) 
	add $t0, $t0, 1 # address++
	add $t1, $t1, -1 # count--
	bgtz $t1, clr

So is the maze suppose to be pre-filled with 0's or 2's?

malugirl4 0 Junior Poster in Training · Answer 18 · 2009-08-15T08:21:01+00:00

malugirl4 0 Junior Poster in Training

14 Years Ago

0's

wildgoose 420 Practically a Posting Shark · Answer 19 · 2009-08-15T08:26:44+00:00

The clear matrix should look like this then...

# Clear Entire Maze Array

	la $t0, maze # load address of maze
	li $t3, 0              # <-- Fill maze with (0)
	li $t1, 144

clr: # repeat if not finished yet.
	sb $t3, 0($t0) 
	add $t0, $t0, 1 # address++
	add $t1, $t1, -1 # count--
	bgtz $t1, clr

malugirl4 0 Junior Poster in Training · Answer 20 · 2009-08-15T08:28:15+00:00

I just wanted to chekc with you before I kept going:

# register to register compares
# Ref: if (( (robot_x == 1) && (robot_y == 2)) || ( (robot_x == 2) && (robot_y == 4)) )
bne $t0,$t1,LineA3 # jump if robot_x <> 1
beq $t5,$t2,LineAOK # jump if robot_y == 2

LineA3: # || ( (robot_x == 2) && (robot_y == 4)) )
bne $t0,$t2, LineB #jump if robot_x <> 2
bne $t5,$t4, LineB #jump if robot_y <> 4

LineAOK: # SUCCESS

la $a0, MsgFallenChasm
li $v0, 4 # specify Print String service
syscall # print heading

la $a0, robot_state
sw $t2,0($a0) # robot_state = 2

# Process new robot positions

j PrtOut

MoveHop: j MoveLoop

Done:

# Next conditional line
# Ref: else if(( (robot_x == 2) && (robot_y == 3)) || ((robot_x == 3) && (robot_y == 4)))
bne $t0,$t1,LineB # jump if robot_x <> 2
beq $t5,$t2,LineBOK # jump if robot_y == 3

LineB: # || ( (robot_x == 2) && (robot_y == 4)) )
bne $t0,$t2,LineC
bne $t5,$t4,LineC

LineBOK: #SUCCESS

la $a0, MsgFallenTrap
li $vo, 4
syscal
la $a0, robot_state
sw $t2, 0 ($a0) #robot_state=2
j prtOut
MoveHop: j MoveLoop

j Done

wildgoose 420 Practically a Posting Shark · Answer 21 · 2009-08-15T08:57:37+00:00

Done: Should be near bottom of file just above the robot_state 4 case code that doesn't exist yet!

# Process new robot positions

j PrtOut

MoveHop: j MoveLoop

Done:

# Next conditional line
# Ref: else if(( (robot_x == 2) && (robot_y == 3)) || ((robot_x == 3) && (robot_y == 4)))

!!!! Remember $t0 is robot_x $t5 is robot_y
!!!! $t1=(1) $t2=(2) $t3=(3) $t4=(4)

!!! this line comment is correct, code isn't! You have wrong immedate value, and you aren't jumping to 2nd half of this line! Remember you had ( A & B ) || (C & D) So only 1/2 has to be true to be successful! So if first half fails, then check the second half.

Re-examine conditionals and your branching. I'm shutting down in a couple minutes to head for home, etc. But...

1st Conditional Line
LineA:
if (A <> #) then go to 2nd half Line A3
if (B == #) Then go to succss for LineA LineAOK
LineA3:
if (C <> #) then go to Line B we totally lose
if (D <> #) then go to Line B we also lose

LineAOK: WINNER
Do our stuff
then jump past everything to DONE which is robot_state case

--------
Line B
For Line B we do same as Line A with new sets of #'s.

------
Line C
Same again

------
Line D
Same again

Done: We are now at robot_state printing!

----------------
Okay review my comments as to your code...
for Line B

bne $t0,$t1,LineB # jump if robot_x <> 2

!!!Comment is correct Code is not!
beq $t5,$t2,LineBOK # jump if robot_y == 3

LineB: # || ( (robot_x == 2) && (robot_y == 4)) )

bne $t0,$t2,LineC # <--- Good
bne $t5,$t4,LineC # <--- Good

LineBOK: #SUCCESS

la $a0, MsgFallenTrap
li $vo, 4
syscal
la $a0, robot_state
sw $t2, 0 ($a0) #robot_state=2
j prtOut ????

!!! remember we keep flowing dowards. In Java it was if else if elseif else

So Need to jump past the other else's to the robot_state case statement code!

j Done

malugirl4 0 Junior Poster in Training · Answer 22 · 2009-08-15T21:57:45+00:00

.data # variable declarations follow this line
iSAFE: 1
iCHASM: 2
iTRAP: 3
iDESTINATION: 4

maze: .space 144 # 9x9 stored in a 16x9 buffer 
robot_x: .word 0
robot_y: .word 0
robot_m_x: .word 0
robot_m_y: .word 0
robot_state: .word 0
robot_instructions: .space 256

# Robot State Message Table
MsgRobotTbl:		
		.word		MsgRS1
		.word		MsgRS2
		.word		MsgRS3
		.word		MsgRS4
		.word		MsgRS5
MsgFailsDestination: .asciiz "Robot fails to reach Destination\n"

MsgRS1: .asciiz "Robot is at a safe place\n" 
MsgRS2: .asciiz "Robot falls into Chasm\n"
MsgRS3: .asciiz "Robot falls into the trap\n"
MsgRS4: .asciiz "Robot reaches Destination\n"
MsgRS5: .asciiz "Robot fails to reach Destination\n"
MsgFinal:	.asciiz "Robot final location X: "
MsgY:		.asciiz " Y: "
MsgCR:		.asciiz "\n"
MsgRobotState:  .asciiz  "Robot State: \n"
MsgFallenChasm:  .asciiz  "Robot has fallen into a chasm\n"
MsgFallenTrap:   .asciiz  "Robot has fallen into a trap\n"
MsgReachedDestination:  .asciiz  "Robot has reached Destination\n"
MsgSafePlace:    .asciiz  "Robot is at a safe place\n"
MsgFallsChasm:	.asciiz   "Robot falls into Chasm\n"
MsgFallsTrap:   .asciiz   "Robot falls into the trap\n"
MsgReachesDestination: .asciiz "Robot reaches Destination\n"

.text # CODE SECTION OF ASM FILE

#main:
li $v0,30 # Get time
syscall # CMD: Get Time
# $a0 = lower 32-bits, $a1=upper 32-bits

# Seed RNG (Random Number Generator)
move $a1,$a0 # get lower 32-bit time as seed
li $a0,0 # Rng#0
syscall # CMD: Seed the RNG


# Clear Entire Maze Array

	la $t0, maze # address of maze
	li $t3, 0              
	li $t1, 144

clr: # repeat if not finished yet.
	sb $t3, 0($t0) 
	add $t0, $t0, 1 # address++
	add $t1, $t1, -1 # count--
	bgtz $t1, clr


	# Setup variables
	la $t0, maze # base address


li $t1,1 # iSAFE: 
sb $t1,0x11($t0) # maze[1][1] = 1;


li $t1,2 # iCHASM:
sb $t1, 0x12($t0) # maze[1][2] = 2    
sb $t1,0x24($t0) # maze[2][4] = 2

li $t1, 3 #iTRAP: 
sb $t1, 0x23($t0) # maze[2][3]
sb $t1, 0x34($t0) # maze[3][4]


li $t1, 4 #iDESTINATION: # maze[3][2] = 4;
sb $t1, 0x32($t0) # 1 x 16 + 4

		# robot_x = 1
	la $t0,robot_x
	li $t1,1
	sw $t1,0($t0)

		# robot_y = 2
	la $t0,robot_y
	li $t1,2
	sw $t1,0($t0)

	# init robot_state = 5
	la $t0,robot_state
	li $t1,5
	sw $t1,0($t0)

	la	$t7,robot_instructions		# index
	li	$t6,64

MoveLoop:


	# Get a Random #

	li $a0, 0 # Rng#
	li $a1, 4 # rand() %4 {0...3}
	li $v0, 42
	syscall # Get RNG
	# $a0 = {0...3}
	add $a0, $a0, 1 # {1...4}

	sw	$a0,0($t7)		# robot_instructions[i] = rnd{ 1...4 }

	add	$a0, $a0, -1
	bgtz $a0,	RJump

		# case 1: MOVE

	la $t1,robot_m_x
	la $t0,robot_x

	lw	$t2,0($t1)
	sw	$t2,0($t0)		# robot_x = robot_m_x

	la	$t1,robot_m_y
	la	$t0,robot_y
	lw	$t2,0($t1)
	add	$t2,$t2,1
	sw	$t2,0($t0)		# robot_y = robot_m_y + 1

	j	PrtOut

	
RJump:
	add	$a0, $a0, -1
	bgtz $a0,	 RLeft

		# case 2: Jump

	la $t1,robot_m_x
	la $t0,robot_x

	lw	$t2,0($t1)
	sw	$t2,0($t0)		# robot_x = robot_m_x

	la	$t1,robot_m_y
	la	$t0,robot_y
	lw	$t2, 0($t1)
	add	$t2, $t2, 2
	sw	$t2, 0($t0)		# robot_y = robot_m_y + 2

	j	PrtOut


RLeft:
	add	$a0, $a0, -1
	bgtz $a0,	RRight

		# case 3: Left

	la $t1,robot_m_x
	la $t0,robot_x
	lw	$t2,0($t1)
	add	$t2, $t2, -1
	sw	$t2,0($t0)		# robot_x = robot_m_x - 1


	j	PrtOut

RRight:

	la $t1,robot_m_x
	la $t0,robot_x
	lw	$t2,0($t1)
	add	$t2, $t2, 1
	sw	$t2,0($t0)		# robot_x = robot_m_x + 1

	#	Process new robot posit5ions!

PrtOut:
		#	System.out.println("Robot final location X: " + robot_x + " Y: " + robot_y);

	la $a0, MsgFinal
	li $v0, 4 				# specify Print String service
	syscall # print heading

	la $t0,robot_x
	lw $a0,0($t0)
	li $v0, 1
	syscall # CMD: print robot x integer

	la $a0, MsgY
	li $v0, 4 				# specify Print String service
	syscall # print heading

	la $t0,robot_y
	lw $a0,0($t0)
	li $v0, 1
	syscall # CMD: print robot Y integer

	la $a0, MsgCR
	li $v0, 4 				# specify Print String service
	syscall # print heading

		#	System.out.println ("Robot State: ");
la $t0,robot_x
  lw $t0,0($t0)           # $t0 = robot_x
  la $t5,robot_y
#  lw $t5,0($t1)           # $t5 = robot_y
  lw $t5,0($t5)           # $t5 = robot_y

# Using $t1 ... $t4 since they look similar to 1...4
  li  $t1,1
  li  $t2,2
  li  $t3,3
  li  $t4,4

  #  register to register compares
  # Ref:  if (( (robot_x == 1) && (robot_y == 2)) || ( (robot_x == 2) && (robot_y == 4)) )
  bne $t0,$t1,LineA3   # jump if robot_x <> 1
  beq $t5,$t2,LineAOK   # jump if robot_y == 2

LineA3:                                              # || ( (robot_x == 2) && (robot_y == 4)) )
  bne $t0,$t2, LineB    #jump if robot_x <> 2
  bne $t5,$t4, LineB    #jump if robot_y <> 4

LineAOK:   # SUCCESS

  la $a0, MsgFallenChasm
  li $v0, 4 				# specify Print String service
  syscall # print heading
  
    la $a0, robot_state
  sw $t2,0($a0)                          # robot_state = 2

	#	Process new robot positions

	j	PrtOut

MoveHop:  j MoveLoop           

# Next conditional line 
# Ref: else if(( (robot_x == 2) && (robot_y == 3)) || ((robot_x == 3) && (robot_y == 4))) 
bne $t0,$t2,LineB # jump if robot_x <> 2 
beq $t5,$t3,LineBOK # jump if robot_y == 3


LineB: 	# || ( (robot_x == 2) && (robot_y == 4)) ) 

bne $t0,$t3,LineC 			#jump if robot_x <> 3
bne $t5,$t4, LineC  	    #jump if robot_y <> 4
 

LineBOK: #SUCCESS

la $a0, MsgFallenTrap
li $vo, 4
syscal#print heading
la $a0, robot_state
sw $t2, 0 ($a0)	#robot_state=3

j MoveLoop

j Done

 

#  register to register compares
 # Ref:  if ((robot_x == 3) && (robot_y == 2))
  bne $t0,$t3,LineC   # jump if robot_x <> 3
  beq $t5,$t2,LineC   # jump if robot_y == 2
     

LineCOK:   # SUCCESS

  la $a0, MsgReachedDestination
  li $v0, 4 				# specify Print String service
  syscall # print heading
  
    la $a0, robot_state
  sw $t2,0($a0)                          # robot_state = 4

	#	Process new robot positions

	j	PrtOut

 j MoveLoop      


j Done 


LineDOK:   # SUCCESS

  la $a0, MsgSafePlace
  li $v0, 4 				# specify Print String service
  syscall # print heading
  
    la $a0, robot_state
  sw $t2,0($a0)                          # robot_state = 1

	#	Process new robot positions

	j	PrtOut


Done:


	jr $ra # return

malugirl4 0 Junior Poster in Training · Answer 23 · 2009-08-15T22:42:28+00:00

Error in Assembly2 line 262 position 4: "$vo": operand is of incorrect type
Error in Assembly2 line 263 position 1: "syscal" directive cannot appear in text segment
Assemble: operation completed with errors.

malugirl4 0 Junior Poster in Training · Answer 24 · 2009-08-15T22:57:27+00:00

Error in Assembly2 line 260 position 5: "$vo": operand is of incorrect type
Error in Assembly2 line 261 position 2: "syscal" directive cannot appear in text segment
Error in Assembly2 line 277 position 5: "$vo": operand is of incorrect type
Error in Assembly2 line 278 position 2: "syscal" directive cannot appear in text segment
Assemble: operation completed with errors.

malugirl4 0 Junior Poster in Training · Answer 25 · 2009-08-15T23:38:06+00:00

#robot_state print

Done:
	la	$a0, robot_state
	lw	$t0,0($a0)		# to is robot_state

	la $a0, robot_state
	sw $t4,0($a0)		# robot_state = 1
	syscall


    la $a0, robot_state
	sw $t2,0($a0)		# robot_state = 2
	syscall


	la $a0, robot_state
	sw $t3, 0 ($a0)		#robot_state=3
	syscall

	la $a0, robot_state
	sw $t4, 0 ($a0)		#robot_state=4
	syscall

malugirl4 0 Junior Poster in Training · Answer 26 · 2009-08-15T23:39:33+00:00

Error in Assembly2 line 260 position 5: "$vo": operand is of incorrect type
Error in Assembly2 line 261 position 2: "syscal" directive cannot appear in text segment
Error in Assembly2 line 277 position 5: "$vo": operand is of incorrect type
Error in Assembly2 line 278 position 2: "syscal" directive cannot appear in text segment
Assemble: operation completed with errors.

malugirl4 0 Junior Poster in Training · Answer 27 · 2009-08-15T23:41:00+00:00

oops typo on the syscall*

But I can't figure out the error in this:

Error in Assembly2 line 260 position 5: "$vo": operand is of incorrect type
Error in Assembly2 line 277 position 5: "$vo": operand is of incorrect type
Assemble: operation completed with errors.

wildgoose 420 Practically a Posting Shark · Answer 28 · 2009-08-16T00:37:16+00:00

I missed it change those two syscal to syscall

Change $vo to $v0 zero

wildgoose 420 Practically a Posting Shark · Answer 29 · 2009-08-16T01:04:42+00:00

You print the four robot_state lines but you aren't printing based upon if 1 or 2 or 3 or 4.

So without using conditionals, try this instead!
It uses the robot_state as an index into a string table and prints the appropriate string for states 1...5

Done:
	la	$a0, robot_state
	lw	$t0,0($a0)          # is state 1...5

	add  $t0,$t0,-1                 # state is 0...4
	sll	$t0,$t0,2			# x4       0,4,8,12,16  Address offset 

		# ASCIIz table lookup
	la	$a0, MsgRobotTbl	# table base
	add	$a0, $a0, $t0
	lw	$a0,0($a0)

	li $vo, 4
	syscal				#print ASCIIz    MsgRobotTbl[ robot_state ]

There's probaby bugs but you should try to find them yourself by single steping the code and watching the values in the registers. If you have compile errors, look for typos, like those last errors you posted!

When you get curious enough, find the line count for your Java program and find the line count for this assembly file. Notice the difference! That's why these days higher level languages are used for application building and not assembly language. Assembly is left for specialty applications like drivers, and math libraries, etc.