mirror of
https://github.com/WangXuan95/USTC-RVSoC.git
synced 2025-01-30 23:02:55 +08:00
34 lines
1.3 KiB
ArmAsm
34 lines
1.3 KiB
ArmAsm
|
.org 0x0
|
|||
|
|
.global _start
|
|||
|
|
_start:
|
|||
|
|
print_hello:
|
|||
|
|
# 第一步：令t0寄存器=0x00030000，即user_uart外设的地址
|
|||
|
|
or t0, zero,zero # t0 清零
|
|||
|
|
lui t0, 0x00020 # t0 寄存器的高20bit=0x00020
|
|||
|
|
|
|||
|
|
# 第二步：将hello!逐个字符写入user_uart外设，即打印hello!到uart
|
|||
|
|
ori t1, zero, 0x068 # t1='h'的ASCII码
|
|||
|
|
sb t1, (t0) # t1写入t0地址
|
|||
|
|
addi t0, t0 , 0x001 # t0+1
|
|||
|
|
ori t1, zero, 0x065 # t1='e'的ASCII码
|
|||
|
|
sb t1, (t0) # t1写入t0地址
|
|||
|
|
addi t0, t0 , 0x001 # t0+1
|
|||
|
|
ori t1, zero, 0x06c # t1='l'的ASCII码
|
|||
|
|
sb t1, (t0) # t1写入t0地址
|
|||
|
|
addi t0, t0 , 0x001 # t0+1
|
|||
|
|
ori t1, zero, 0x06c # t1='l'的ASCII码
|
|||
|
|
sb t1, (t0) # t1写入t0地址
|
|||
|
|
addi t0, t0 , 0x001 # t0+1
|
|||
|
|
ori t1, zero, 0x06f # t1='o'的ASCII码
|
|||
|
|
sb t1, (t0) # t1写入t0地址
|
|||
|
|
addi t0, t0 , 0x001 # t0+1
|
|||
|
|
ori t1, zero, 0x021 # t1='!'的ASCII码
|
|||
|
|
sb t1, (t0) # t1写入t0地址
|
|||
|
|
|
|||
|
|
# 第三步：延时，通过大空循环的方式
|
|||
|
|
lui t2, 0x00c00 # t2 = 0x00c00000
|
|||
|
|
big_loop:
|
|||
|
|
addi t2, t2, -1 # t2 = t2-1
|
|||
|
|
bne t2, zero, big_loop # if t2!=0, jmp to big_loop
|
|||
|
|
jal zero, print_hello # 大循环结束，跳到print_hello，重复打印
|