Could you recode this Ceasar cipher from LC-3 to Mips (Mars) assembly code? Thank you

;the ceasar cipher asks user for encrypt or decrypt

;it will encrypt or decrypt user input string by shifting

;by a user chosen number

; main code

.ORIG x3000

; greeting

LD R0, greetingAddr

PUTS

greetingAddr .FILL greeting

;clear all registers

Start AND R0, R0, 0

STI R0, cryptAddr

STI R0, keyAddr

AND R0, R0, 0

AND R1, R0, 0

AND R2, R0, 0

AND R3, R0, 0

AND R4, R0, 0

AND R5, R0, 0

AND R6, R0, 0

AND R7, R0, 0

cryptAddr .FILL crypt

keyAddr .FILL key

; ask user to choose encrypt, decrypt, or exit

LD R0, askCryptAddr

PUTS ; print prompt string

LD R0, newlineAddr ; new line

PUTS

Loop1 GETC

OUT

; check if user wants to exit

LD R1, negOfx

ADD R1, R0, R1 ; check if hit x

BRz EndProgram

; check if user wants to encrypt

LD R1, negOfe

ADD R1, R0, R1 ; check if e

BRz SetToEncrypt

; check if user wants to decrypt

LD R1, negOfd

ADD R1, R0, R1 ; check if d

BRz SetToDecrypt

BR Loop1

SetToEncrypt AND R1, R1, 0 ; clear R1

ST R1, crypt ; set crypt to 0 (Encrypt)

BR InputCipherKey

SetToDecrypt AND R1, R1, 0 ; clear R1

ADD R1, R1, #1 ; add 1

ST R1, crypt ; set crypt to 1 (Decrypt)

BR InputCipherKey ; next

askCryptAddr .FILL askCrypt ; indirect

newlineAddr .FILL newline

; ask user to input cipher shift key (the value to shift by, between 1-25)

InputCipherKey LD R0, askShiftAddr

PUTS

LEA R0, newline ; load newline with > symbol

PUTS

JSR NumberInput ; outputs number input to R1

ST R0, key ; store number input into key

BR InputString ; next

askShiftAddr .FILL askShiftkey

; ask user for the string

InputString LD R0, askStrAddr

PUTS

LEA R0, newline

PUTS

AND R1, R1, 0 ; R1 is column

AND R2, R2, 0 ; R2 is row

Loop2 GETC

ADD R4, R0, #-10 ; negative of line feed

BRz Null1 ; if user hit Enter, go to null

OUT

JSR Store ; Input: R0 data, R1 row, R2 column

ADD R1, R1, #1 ; go to next column

BR Loop2

Null1 LD R0, nullChar

JSR Store ; already at next space

BR CheckCrypt ; next

askStrAddr .FILL askString

; Encrypt or decrypt the string

CheckCrypt LD R0, crypt ; check encrypt or decrypt

BRz LetsEncrypt ; if crypt=0 then encrypt

BRp LetsDecrypt ; if crypt=1 then decrypt

LetsEncrypt JSR Encrypt ; encrypt the input

BR LetsPrint

LetsDecrypt JSR Decrypt ; decrypt it

LetsPrint BR PrintString

; Print the string

PrintString JSR PrintArray

BR Start ; loop to restart

EndProgram LD R0, byeExtra ; End program

PUTS

HALT

byeExtra .FILL bye

;end of main program code

;@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@

; SUBROUTINES START HERE

; NumberInput

; this subroutine converts ASCII to decimal

; if user input a number, console will print the number back out

NumberInput ST R7, saveR7_1 ; Save R7 since TRAPS overwrite it

LD R4, asciiToDec

AND R0, R0, 0

ST R0, NumberIn

InLoopSR1 GETC

ADD R1, R0, #-10 ; check if user hit Enter or line feed

BRz DoneInputValue ; if user hit Enter, end input value

OUT

ADD R0, R0, R4 ; convert ascii input to decimal value

LD R1, NumberIn ; load user input value

; multiply by ten

AND R3, R3, 0 ; R3 used to store

ADD R2, R2, #10 ; set counter to 10 to multiply 10 times

Mult BRz EndMult

ADD R3, R3, R1 ; do multiplcation

ADD R2, R2, #-1 ; decrease the counter

BR Mult

EndMult ADD R1, R3, R0 ; add user value input + entered char decimal value

ST R1, NumberIn

BR InLoopSR1

DoneInputValue LD R7, saveR7_1 ; load R7 with correct return address

LD R0, NumberIn ; load user input to return

RET

NumberIn: .FILL 0

saveR7_1: .FILL 0

; Encrypt

; Input: None

; Output: None

Encrypt ST R7, saveR7_3

; calculate load address

AND R1, R1, 0 ; R1 is column

AND R2, R2, 0 ; R2 is row

ST R1, CountColmn ; set column count to 0

EncryptLoop AND R2, R2, 0 ; go to row 0

LD R1, CountColmn ; go to correct column

JSR Load ; R0 is data output

ADD R0, R0, 0 ; will be 0 if char is null

BRz NullSR1 ;

LD R1, key ; load key

JSR PerformEncrypt ; encrypt the char

; calculate store address

AND R2, R2, 0

ADD R2, R2, #1 ; go to row 1

LD R1, CountColmn ; go to correct column

JSR Store ; store data in (row 1, CountColmn)

;this stores encrypted characters into last row

LD R1, CountColmn ; load to iterate column

ADD R1, R1, #1 ; go to next column over

ST R1, CountColmn ; store column counter

BR EncryptLoop

NullSR1 LD R0, nullChar

AND R2, R2, 0 ; R1 is row

ADD R2, R2, #1 ; go to row 1

JSR Store ; column R1 already at next space

LD R7, saveR7_3

RET

CountColmn .FILL 0 ; counts the columns of each row

saveR7_3: .FILL 0 ; save R7 for return

; Decrypt

; Input: None

; Output: None

Decrypt ST R7, saveR7_4 ;save R7

AND R1, R1, 0 ; R1 is row

AND R2, R2, 0 ; R2 is column

ST R1, CountColmn2 ; set column count to 0

DecryptLoop AND R2, R2, 0 ; go to row 0

LD R1, CountColmn2 ; go to correct column

JSR Load ; R0 is data output

ADD R0, R0, 0 ; will be 0 if char is null

BRz NullSR2

LD R1, key ; load the key

JSR PerformDecrypt ; encrypt the char

; calculate store address

AND R2, R2, 0

ADD R2, R2, #1 ; go to row 1

LD R1, CountColmn2 ; go to correct column

JSR Store ; store data in (row 1, colmnCount2)

LD R1, CountColmn2 ; load to move column

ADD R1, R1, #1 ; go to next column over

ST R1, CountColmn2 ; store column counter

BR DecryptLoop

NullSR2 LD R0, nullChar

AND R2, R2, 0 ; R2 is row

ADD R2, R2, #1 ; go to row 1

JSR Store ; column R1 already at next space

LD R7, saveR7_4

RET

CountColmn2 .FILL 0 ; iterator count for moving columns

saveR7_4: .FILL 0 ; save R7 for return

; Perform the actual encryption

; Input: R0, the char. R1, the shift key

; Output: R0, the encrypted char.

PerformEncrypt

; first test the inputs

; test if input is uppercase

LD R2, negOfA

ADD R3, R0, R2

BRn FinEncrypt ; not abc char

LD R2, negOfZ

ADD R3, R0, R2

BRnz UppercaseEncrp

; test if input is lowercase

LD R2, negOfa

ADD R3, R0, R2

BRn FinEncrypt ; if negative, then input was not a abc character

LD R2, negOfz

ADD R3, R0, R2

BRnz LowercaseEncrp

BRp FinEncrypt

UppercaseEncrp ADD R0, R0, R1 ; perform encryption

LD R2, negOfZ

ADD R3, R0, R2

BRnz FinEncrypt ; no extra, so end

; add the extra if there is any

LD R4, A ; load uppercase A

ADD R0, R3, R4 ; add the extra difference to A

; then subtract 1 and end

ADD R0, R0, #-1 ; subtract 1 (ex: if there is extra of 1, then subtract it

; to loop back to original character)

BR FinEncrypt

LowercaseEncrp ADD R0, R0, R1 ; perform encryption

; check if went past lowercase z

LD R2, negOfz

ADD R3, R0, R2

BRnz FinEncrypt ; if less than or equal zero, then no extra, so end

; if so, subtract difference and add to a

LD R4, a ; load lowercase a

ADD R0, R3, R4 ; add the extra difference to a

ADD R0, R0, #-1 ; subtract 1

BR FinEncrypt

FinEncrypt RET

; Perform the actual decryption

; Input: R0, the char . R1, the shift key

; Output: R0, the decrypted char.

PerformDecrypt NOT R1, R1 ; perform 2's Complment

ADD R1, R1, #1 ; turn key into negative

; is char uppercase

LD R2, negOfA

ADD R3, R0, R2

BRn FinDecrypt ; not alphabetical char

LD R2, negOfZ

ADD R3, R0, R2

BRnz UppercaseDcryp

; is char lowercase

LD R2, negOfa

ADD R3, R0, R2

BRn FinDecrypt ; not alphabetical char

LD R2, negOfz

ADD R3, R0, R2

BRnz LowercaseDcryp

BRp FinDecrypt ; not alphabetical char

UppercaseDcryp ADD R0, R0, R1 ; perform decryption

; check if went below uppercase A

LD R2, negOfA

ADD R3, R0, R2

BRzp FinDecrypt ; if greater or equal to zero, then no extra, so end

; if so, use the difference and subtract from Z

LD R4, Z

ADD R0, R3, R4 ; subtract the extra from Z

; then add 1 and end

ADD R0, R0, #1 ; add 1 to the value

BR FinDecrypt

LowercaseDcryp ADD R0, R0, R1 ; perform decryption

; check if went below lowercase a

LD R2, negOfa

ADD R3, R0, R2

BRzp FinDecrypt ; if less than or equal, then no extra, so end

; if so, use the difference and subtract from z

LD R4, z ; load lowercase z

ADD R0, R3, R4 ; subtract the extra from z

ADD R0, R0, #1 ; add 1

BR FinDecrypt

FinDecrypt RET

a .FILL #97

negOfa .FILL #-97

z .FILL #122

negOfz .FILL #-122

A .FILL #65

negOfA .FILL #-65

Z .FILL #90

negOfZ .FILL #-90

; Store

; this stores data into CIPHER_ARRAY

; Input: R0, ASCII character to store. R1, the column. R2, the row

; Output: None

Store LD R3, CipherAddr

ADD R4, R2, #-1 ; check which row

BRn SkipSR1 ; if first row, then skip

LD R4, fifty ; R4 = 50

ADD R3, R3, R4 ; calculate the row

SkipSR1 ADD R3, R3, R1 ; calculate the column

STR R0, R3, #0 ; store

RET

; Load

; this subroutine loads data from CIPHER_ARRAY

; Input: R1, the column. R2, the row.

; Output: R0, contents of CIPHER_ARRAY

Load LD R3, CipherAddr

ADD R4, R2, #-1 ; check which row

BRn SkipSR2 ; if first row, then skip

LD R4, fifty ; fifty is # of columns in a row

ADD R3, R3, R4 ; calculate the row

SkipSR2 ADD R3, R3, R1 ; calculate the column

LDR R0, R3, #0 ; load data into R0

RET

CipherAddr .FILL CIPHER_ARRAY ; indirect

; PrintArray

; this subroutine prints out encrypted/decrpyed strings

PrintArray ST R7, saveR7_2 ; Save R7

LD R0, crypt

BRz PrintEncrypt ; if crypt=0, encrypt

PrintDecrypt LEA R0, encryptedStr

PUTS

LEA R0, CIPHER_ARRAY

PUTS

LEA R0, decryptedStr

PUTS

LEA R0, CIPHER_ARRAY

LD R1, fifty ; R1 = 50

ADD R0, R0, R1 ; go to next row (add 50)

PUTS

BR DonePrint

PrintEncrypt LEA R0, decryptedStr

PUTS

LEA R0, CIPHER_ARRAY

PUTS

LEA R0, encryptedStr

PUTS

LEA R0, CIPHER_ARRAY

LD R1, fifty ; R1 =50

ADD R0, R0, R1 ; go to next row (add 50)

PUTS ; print encrypted text

BR DonePrint

DonePrint LD R7, saveR7_2

RET

saveR7_2: .FILL 0 ; save R7

crypt: .FILL 0 ; 0 is encrypt; 1 is decrypt

key: .FILL 0

negOfx: .FILL -120 ; use to test if x entered

negOfd: .FILL -100 ; use to test of d entered

negOfe: .FILL -101 ; use to test if e entered

ascii: .FILL 48 ; decimal to ascii

asciiToDec: .FILL -48 ; ascii to decimal

nullChar: .FILL 0 ; counts as null char

fifty: .FILL 50 ; 2x50 array

newline: .STRINGZ " > "

greeting: .STRINGZ " Hi, welcome to my Caesar Cipher program"

askCrypt: .STRINGZ " Do you want to (e) ncrypt, (d)ecrypt, or e(x)it?"

askShiftkey: .STRINGZ " What's the cipher shift key (1-25)?"

askString: .STRINGZ " What's the string? (up to 50 chars)"

bye: .STRINGZ " See Ya!"

encryptedStr: .STRINGZ " Encrypted: "

decryptedStr: .STRINGZ " Decrypted: "

CIPHER_ARRAY .BLKW 100 ; 2D array, row major

.END