diff options
Diffstat (limited to 'examples/hello_world.subv')
| -rw-r--r-- | examples/hello_world.subv | 17 |
1 files changed, 9 insertions, 8 deletions
diff --git a/examples/hello_world.subv b/examples/hello_world.subv index f74bc64..25a1cba 100644 --- a/examples/hello_world.subv +++ b/examples/hello_world.subv @@ -1,4 +1,4 @@ -== code 0x80400000 +== code 0x0 # load mhartid CSR into t0, trap all but first Hart # 73/system 5/rd/t0 2/funct3/csrrs 0/rs/x0 f14/csr/mhartid # 63/branch 1/subop/!= 5/rs/t0 0/rs/x0 0/off13 @@ -13,6 +13,7 @@ main: 6f/jal 1/rd/ra print/off21 exit: + 6f/jal 0/rd/x0 main/off21 # system reset (via SBI extension SRST) # a7 = ext id, a6 = fid, a0 = 0, a1 = 0 37/lui 11/rd/a7 53525/imm20 @@ -24,20 +25,20 @@ exit: 73/system 0/subop/priv 0/funct12/ecall print: - # load 0x10000000 (UART0) into t0 - 37/lui 5/rd/t0 10000/imm20 + # load 0x20000 (UART0) into t0 + 37/lui 5/rd/t0 20/imm20 print:loop: # load unsigned byte at a0 03/load 6/rd/t1 4/width/bu 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 7/rd/t2 4/width/bu 5/rs/t0 5/imm12 - 13/opi 7/rd/t2 7/subop/and 7/rs/t2 20/imm12 + # spin if FIFO is full (UART+4 & 1 == 0) + 03/load 7/rd/t2 2/width/w 5/rs/t0 4/imm12 + 13/opi 7/rd/t2 7/subop/and 7/rs/t2 1/imm12 63/branch 0/subop/== 7/rs/t2 0/rs/x0 print:spin/off13 # print char - 23/store 2/width/w 5/rs/t0 0/off12 6/rs/t1 + 23/store 2/width/w 5/rs/t0 8/off12 6/rs/t1 # increment a0 13/opi a/rd/a0 0/subop/add a/rs/a0 1/imm12 # jump back up @@ -46,7 +47,7 @@ print:break: # return 67/jalr 0/rd/x0 0/subop 1/rs/ra 0/off12 -== data 0x80500000 +== data 0x100 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 |