MTC1 - MIPS instruction reference

mtc1Move from integer register to FP register 
Copies the 32-bit value in integer register $t1 into FP register $f1 without any conversion.
Used in Floating point and Coprocessor 1MIPS assembly
 
Forms  mtc1 ,   
Operands $t1 Any general-purpose register, $0 to $31, using its numeric or named spelling, such as $8 or $t0 ($zero is $0; $ra is $31). 
$f1 Any floating-point register, $f0 to $f31. 
Useful for initializing a FP register with a specific bit pattern or loading a freshly-computed integer before 'cvt.s.w'.
 # Copy the raw bit pattern for 1.0 into $f0. Inspect $f0: 0x3F800000.
li $t0, 0x3F800000
mtc1 $t0, $f0