MIPS how can you compare a character taken from input?

Question

Hello,

My program asks the user if the number he/she is thinking of is in a list. The user inputs a y or an n. How can I check if a user has entered y or n in assembly? Is it sufficient to put the user input into a register and branch if equal to 121 (decimal ASCII code for 'y') or branch if the value is equal to 110 (decimal ASCII code for 'n'?

Thanks in advance

Answer 1

One can use the system call code for Read Character, which should be system call code 12, then the character (binary ASCII code) will be stored in $v0. Then you can make a register equal to 121 and another to 110. Then branch if equal.

SPIM system call codes: http://www.doc.ic.ac.uk/lab/secondyear/spim/node8.html