Please help with this MIPs assembly code

CSE 230 Project 3: UART Palindrome CheckerLearning Objectives:

Create modular code and interface with unfamiliar modularized code

The Task

In this project, you will be writing a program that receives a string of characters via the UART, checks if this string is a palindrome, and then uses a print function to print either Yes or No. A palindrome sequence of characters (typically a word or phrase) that is the same both forwards and backwards. For this project, stringswill be terminated using a period (.). You may assume that a string will contain at least one character in addition to a period. You will not need to handle empty strings or strings with only a period. Your program should be able to handle multiple strings sent one after another or concatenated together. For example, thestring: abba. data. should print Yes followed by No on the next line. Spaces should be ignored when checking for a palindrome and the palindrome should not be case sensitive. For example, A nut for a jar of Tuna. would be considered a palindrome.

Print Function

A skeleton PLP project file is available to download on Blackboard. The PLP project includes a second ASMfile titled, project3_print.asm. This ASM file contains the print function used in this project. PLPTool concatenates allASM files within a PLP project into a single location in memory (unless additional .orgstatements have been added to specify different location for code). No changes to project3_print.asmshould be made.

When called, depending on the value in register $a0, the following string will be displayed on the simulatedUART devices output. If $a0 contains a zero then No will be displayed and if $a0 contains a non-zero value (e.g. one) then Yes will be displayed. The print function is called using the following instruction:

To use the print function, your PLP program needs to initialize the stack pointer ($sp) before performing the function call (or any other operations involving the stack pointer). For this reason, the skeleton project file includes an initialization that sets the stack pointer to 0x10fffffc (the last address of RAM).

call project3_print

Deliverables:

Submit your program on Blackboard with the format: lastname_project3.plp (21 points)

SKELETON FILE

main.asm

.org 0x10000000

# Initializations li $sp, 0x10fffffc

# Initialize any registers you will be using here. # It can be helpful to include a comment about a register's purpose # next to an initialization at the start of the program for reference.

j main nop

array_ptr: # Label pointing to 100 word array .space 100

main: # TODO: write your primary program within this loop

j main nop

project3_print.asm

li $a0, control_message_p3 jal libplp_uart_write_string_p3 nop control_flow_trap_p3: j control_flow_trap_p3 nop

string_yes_p3: .asciiz "Yes "

string_no_p3: .asciiz " No "

control_message_p3: .asciiz "Error: Program entered project3_print.asm due to missing control flow at the end of main.asm "

project3_print: push $ra bne $a0 $0, set_ptr_yes nop li $a0, string_no_p3 j print_string_p3 nop set_ptr_yes: li $a0, string_yes_p3

print_string_p3: jal libplp_uart_write_string_p3 nop pop $ra return

# From PLP UART Library

libplp_uart_write_p3: lui $t0, 0xf000 #uart base address libplp_uart_write_loop_p3: lw $t1, 4($t0) #get the uart status andi $t1, $t1, 0x01 #mask for the cts bit beq $t1, $zero, libplp_uart_write_loop_p3 nop sw $a0, 12($t0) #write the data to the output buffer sw $t1, 0($t0) #send the data! jr $31 nop

libplp_uart_write_string_p3: #we have a pointer to the string in a0, just loop and increment until we see a \0 move $t9, $31 #save the return address move $t8, $a0 #save the argument libplp_uart_write_string_multi_word_p3: lw $a0, 0($t8) #first 1-4 characters ori $t0, $zero, 0x00ff #reverse the word to make it big endian and $t1, $t0, $a0 #least significant byte sll $t1, $t1, 24 srl $a0, $a0, 8 and $t2, $t0, $a0 #second byte sll $t2, $t2, 16 srl $a0, $a0, 8 and $t3, $t0, $a0 #third byte sll $t3, $t3, 8 srl $a0, $a0, 8 #last byte in a0 or $a0, $t1, $a0 or $a0, $t2, $a0 or $a0, $t3, $a0 beq $a0, $zero, libplp_uart_write_string_done_p3 nop ori $t7, $zero, 4 libplp_uart_write_string_loop_p3: jal libplp_uart_write_p3 #write this byte addiu $t7, $t7, -1 srl $a0, $a0, 8 bne $a0, $zero, libplp_uart_write_string_loop_p3 nop beq $t7, $zero, libplp_uart_write_string_multi_word_p3 addiu $t8, $t8, 4 #increment for the next word libplp_uart_write_string_done_p3: jr $t9 #go home nop

Will rate!! thank you for the help!!