code: def PMINUB(cpu, dest, src):
          
          dest_value = dest.read()
          src_value = src.read()
          result = 0
          for pos in range(0, dest.size, 8):
              itema = (dest_value >> pos) & 0xff
              itemb = (src_value >> pos) & 0xff
              result |= Operators.ITEBV(dest.size, itema < itemb, itema, itemb) << pos
          dest.write(result)
docs: PMINUB: returns minimum of packed unsigned byte integers in the dest operand
          see PMAXUB