Here is a quick way for you to decode a one hot state value into a binary representation. This code is built for the MIPS32 architecture.
/************************************* * One-Hot Decoder * Usage: Convert the lower nibble of a 32bit * one hot active low to a binary number * representing the bit position. * Input: $a0 for the hot value (IE: 0b1101) * Output: $v0 is the decoded value (IE: 0x1) *************************************/ .ent one_hot_decode one_hot_decode: //Invert the incoming ( Remove if Active High ) xori $a0, $a0, 0xF //Count the number of leading zeros clz $t1, $a0 //v0 = 31 - #zeros li $t0, 31 subu $v0, $t0, $t1 jr $ra nop .end one_hot_decode