.eqv SEVENSEG_LEFT 0xFFFF0011 # Dia chi cua den led 7 doan trai. 
                # Bit 0 = doan a; # Bit 1 = doan b; ... 
                # Bit 7 = dau . 
.eqv SEVENSEG_RIGHT 0xFFFF0010 
                # Dia chi cua den led 7 doan phai 
.text 
main: 
    li $a0, 0x6 # set value for segments 
    jal SHOW_7SEG_LEFT # show 
    li $a0, 0x7F # set value for segments 
    jal SHOW_7SEG_RIGHT # show 

exit: li $v0, 10 
    syscall 

endmain: 
#--------------------------------------------------------------- 
# Function SHOW_7SEG_LEFT : turn on/off the 7seg 
# param[in] $a0 value to shown # remark $t0 changed 
#--------------------------------------------------------------- 
SHOW_7SEG_LEFT: li $t0, SEVENSEG_LEFT # assign port's address 
    sb $a0, 0($t0) # assign new value 
    jr $ra #--------------------------------------------------------------- 
# Function SHOW_7SEG_RIGHT : turn on/off the 7seg 
# param[in] $a0 value to shown # remark $t0 changed 
#--------------------------------------------------------------- 
SHOW_7SEG_RIGHT: li $t0, SEVENSEG_RIGHT # assign port's address 
    sb $a0, 0($t0) # assign new value 
    jr $ra

display can but i dont know how to hit a button then display it.