Assembly Programming (MIPS): Convert BCD to Decimal

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Margarita0076
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Homework Statement
Write an assembly program to read a four character BCD number from the user. This will be read in as a standard integer. However, you are to convert this number to its BCD equivalent, and print out this decimal number. You can assume that the input is always 4 characters and is legal (i.e. only the digits from 0-9 will appear).
Relevant Equations
Here’s an example:
User types in 8762. This is stored in the computer as 100010001110102
We need to convert it to the representation 1000 0111 0110 0010, which is BCD for 8762 (Notice the first 4 bits has an 8, the next 4 bits has a 7, and so on)
Print out that BCD value (10000111011000102) as a decimal: 34658 (Your syscall print_int does this anyway).

Output:
BCD: 8762
Binary: 34658
I have this code which convert decimal number to binary number, but I do not understand how representation 8762 like 1000 0111 0110 0010.
8​
7​
6​
2​
1000​
0111​
0110​
0010​
Code:
     .data
strmsg: .asciiz "please Enter a decimal number: "
     .text
#main method
.globl main
#main function
main:
    #load the value
    li $v0, 4
    #load the string message
    la $a0, strmsg
    syscall
    # read the value 5
    li $v0, 5
    #syscall method
    syscall
    add $t0, $zero, $v0
    # loop
    li $t1, 31

Loop:
    blt $t1, 0, EndLoop
    srlv $t2, $t0, $t1
    and $t2, 1
    #load value 1
    li $v0, 1
    move $a0, $t2
    syscall

    #substract 1.
    sub $t1, $t1, 1
    b Loop

EndLoop:
    #load the value
    li $v0, 10
    #end
    syscall
 
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Welcome to PF.
Margarita0076 said:
I have this code which convert decimal number to binary number, but I do not understand how representation 8762 like 1000 0111 0110 0010.
8762 base 10, convert to binary is 0010001000111010 base 2.
8192 + 512 + 32 + 16 + 8 + 2 = 8762
 
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Margarita0076 said:
I have this code which convert decimal number to binary number, but I do not understand how representation 8762 like 1000 0111 0110 0010.
Each decimal digit in 8762 is converted to its 4-bit binary form.
8 = 1000
7 = 0111
6 = 0110
2 = 0010
Is that your question, or are you asking how to take an arbitrary decimal integer and represent it in BCD (binary coded decimal)? If this is really your question, you can do this by stripping off each decimal digit and converting it to a 4-bit binary value.
 
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