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== code 0x80400000
# trap all but first Hart (a0 = mhartid)
# 63/branch 1/subop/!= a/rs/a0 0/rs/x0 0/off13
main:
# a0 = &message
# . load high bits
37/lui a/rd/a0 Message/imm20hi
# . add low bits
13/opi 0/subop/add a/rd/a0 a/rs/a0 Message/imm12lo
# call print
6f/jal 1/rd/ra print/off21
loop:
# infinite loop
6f/jal 0/rd/x0 main/off21
print:
# load 0x10000000 (UART0) into t0
37/lui 5/rd/t0 0x10000/imm20
print:loop:
# load unsigned byte at a0
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 (thr_emtpy = UART+5 & 0x20)
03/load 4/subop/byte 7/rd/t2 5/rs/t0 5/imm12
13/opi 7/subop/and 7/rd/t2 7/rs/t2 20/imm12
63/branch 0/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 a0
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
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