How to load memory address without using pseudo-instructions?

Question

I\'m trying to learn MIPS assembly language by myself using MARS simulator.

For didactic reasons I\'m limiting myself to not using pseudo-instructio

Answer 1

Your ori instructions needs still another operand to work and as far as I looked over your code, "mem" is no existing label. Try this one:

.data 0x10000000 #or choose any other location
        #pointer section
        .word arr
        #...

        #pointed section
arr:    .byte #...  only as tip, you can separate multiple values with comma
              #behind .byte so that you don't need multiple .byte directives 
        #...

.text
        #...
        lui $s0, 0x1000
        lw $t0, 0($s0)           #get the value of "arr"
        #...

If it doesn't work, MARS likely won't be able to get label content without pseudo instructions.