== code 0x80000000
  # load mhartid CSR into t0, trap all but first Hart
  73/system 5/rd/t0 2/funct3/csrrs 0/rs/x0 f14/imm12/mhartid 
  63/branch 1/subop/!= 5/rs/t0 0/rs/x0 0/off13

main:
  # x4 = &message
  # . load high bits
  37/lui a/rd/a0 Message/imm20hi
  # . add low bits
  13/opi 0/subop/add 4/rd/x4 a/rs/a0 Message/imm12lo
  # call print
  6f/jal 1/rd/ra print/off21
loop:
  # infinite loop
  6f/jal 0/rd/x0 loop/off21

print:
  # load 0x10010000 (UART0) into t0
  37/lui 5/rd/t0 0x10010/imm20
print:loop:
  # load unsigned byte at x4
  03/load 4/subop/byte 6/rd/t1 a/rs/a0 0/imm12
  # break loop if zero
  63/branch 0/subop/== 6/rs/t1 0/rs/x0 print:break/off13
print:spin:
  # spin if FIFO is full
  03/load 2/subop/word 7/rd/t2 5/rs/t0 0/imm12
  63/branch 4/subop/< 7/rs/t2 0/rs/x0 print:spin/off13
  # print char
  23/store 2/width/word 5/rs/t0 6/rs/t1 0/off12
  # increment x4
  13/opi 0/subop/add a/rd/a0 a/rs/a0 1/imm12
  # jump back up
  6f/jal 0/rd/x0 print:loop/off21
print:break:
  # return
  67/jalr 0/subop 0/rd/x0 1/rs/ra 0/off12

== data 0x80500000
Message:
  # "Hello World!\n\0"
  48/8 65/8 6c/8 6c/8 6f/8 20/8 77/8 6f/8 72/8 6c/8 64/8 21/8 0a/8 00/8