# Luc Sheltons Basic MIPS Player

.data # Data that is used within the MIPS file


copyright: .asciiz "Developed by Luc Shelton\n"

file: .asciiz "menu-main-theme-gm-.luc"
msgOne: .asciiz "Name of the file: "

.align 0
buffer:
.space 102400

.text # Rest of the code
main:


# Register Reference
# t8 - The max iterator, make sure to change this when the file has been loaded in
# t9 - The iterator, this amount will increase once the play loop has been made

# v0 - Type of syscall that is being made

# Load the instruments at the top here

openFile:

# Printing out the filename with "Name of the file: " prior to it
la $a0, copyright
jal printString

la $a0, msgOne # Print "Name of the file: "
jal printString

la $a0, file # Print "crawling.luc"
jal printString

  # OPEN THE FILE AND STORE THE ASCIIZ AS FILE NAME

  # Open (for reading a file that does not exist
  li   $v0, 13       # system call for open file
  la   $a0, file     # output file name
  li   $a1, 0        # Open for writing (flags are 0: read, 1: write)
  li   $a2, 0        # mode is ignored
  syscall            # open a file (file descriptor returned in $v0)
  move $s6, $v0      # save the file descriptor - copying $v0 to $s6

  # LOAD THE FILE INTO MEMORY!

  li	$v0, 14	     # Assigning the syscall to read the file into memory
  move	$a0, $s6     # File descriptor - Getting the file name
  la	$a1, buffer  # Puts the file into buffer
  li	$a2, 104200    # Hardcoding the buffer size
  syscall

  # Close the file
  li   $v0, 16       # system call for close file
  move $a0, $s6      # file descriptor to close
  syscall            # close file


la $k0,buffer # Load the buffer into memory.


# Decide how the player is going to get set up

jal loadnotecount
addi $k0,$k0,1

li $t8, 15 # Iterator max
li $t9, 0 # The iterator

loadchannels: # This loop is made to load all the instruments into the channels
li $v0, 38 # Loading up syscall 38, changes channels instruments
addi $a0, $t9, 0 # Define channel
lb $a1, 0($k0) # Load the instrument from $k0 at the given pointers location
syscall

addi $k0, $k0, 1 # Move the pointer along in the memory address
addi $t9, $t9, 1 # Increase the channel instrument iterator

bne $t8,$t9, loadchannels # If the iterator is not equal to 15 carrying on looping through the load chanels

li $t8, 0
li $t9, 0

addi $k0,$k0,1 # Increase the pointer again

# BYTE ORDER
# 1: CHANNEL

#IGNORE
# 2: DURATION BYTE 1
# 3: DURATION BYTE 2
# 4: DURATION BYTE 3
# 5: DURATION BYTE 4

# 3: PITCH
# 4: VOLUME
# 5: SLEEPTIME

# 11: VOLUME

li $t2, 0 # Iterator

play:
li $v0, 37
lb $a2, 0($k0) # CHANNEL # as thats the first thing that's written to binary
beq $a2, -1, exit
addi $k0, $k0, 1 # Move the pointer along one.
jal loadduration
addi $k0, $k0, 1

lb $a0, 0($k0) # PITCH / KEY
addi $k0, $k0, 1

lb $a3, 0($k0) # VOLUME / VELOCITY
addi $k0, $k0, 1

syscall

# Go to SLEEEEP until the next note D:
li $v0, 32
#addi $k0, $k0, 1
jal loadsleep
addi $k0, $k0, 1 # Push the pointer forward for the next time around
syscall

# Increase the counter
addi $t2, $t2, 1

bne $t2,$t0, play


# Enter player code
#addiu $t9, $t9, 1 # Adds one onto the iterator

#syscall
#jr $ra # Go back to return address


#bne $t8, $t9, play

jal exit

loadduration:
#addi $s1, $0, 0
#lb $s1, 0($k0)
#mul $s1, $s1, $s2

lbu $s1, 0($k0) # Load the first byte of the duration
addi $k0, $k0, 1
lbu $s2, 0($k0) # Load the second byte of the duration
addi $k0, $k0, 1
lbu $s3, 0($k0) # Load the third byte of the duration
addi $k0, $k0, 1
lbu $s4, 0($k0) # Load the fourth and last byte of the duration

mul $s1, $s1, $s2 # Multiply the second and the first byte together
mul $s1, $s1, $s3 # Multiply the result of the two with the third byte

# Add the last byte onto the total
add $s1, $s1, $s4

move $a1, $s1 # Now that all the multiplication is done, lets move it back!
jr $ra

loadsleep:
#li $s1, 0
#lb $s1, 0($k0)
#mul $s1, $s1, $s3

lbu $s1, 0($k0) # Load the first byte of the duration
addi $k0, $k0, 1
lbu $s2, 0($k0) # Load the second byte of the duration
addi $k0, $k0, 1
lbu $s3, 0($k0) # Load the third byte of the duration
addi $k0, $k0, 1
lbu $s4, 0($k0) # Load the fourth and last byte of the duration

mul $s1, $s1, $s2 # Multiply the second and the first byte together
mul $s1, $s1, $s3 # Multiply the result of the two with the third byte

# Add the last byte onto the total
add $s1, $s1, $s4

move $a0, $s1 # Now that all the multiplication is done, lets move it back!
jr $ra

# End the duration loading

loadnotecount:
lbu $s1, 0($k0) # Load the first byte of the duration
addi $k0, $k0, 1
lbu $s2, 0($k0) # Load the second byte of the duration
addi $k0, $k0, 1
lbu $s3, 0($k0) # Load the third byte of the duration
addi $k0, $k0, 1
lbu $s4, 0($k0) # Load the fourth and last byte of the duration

mul $s1, $s1, $s2 # Multiply the second and the first byte together
mul $s1, $s1, $s3 # Multiply the result of the two with the third byte

# Add the last byte onto the total
add $s1, $s1, $s4

move $t0, $s1 # Now that all the multiplication is done, lets move it back!
jr $ra

printString:
li $v0, 4 # Assigning the "Print String" Syscall
syscall
jr $ra # Hop back to where it was called

exit: # Leave the program and set the default values back
addi $v0,$0, 10 # Syscall 10 - terminate and leave the program
syscall