adda_isr.asm

C8051FTest.rar 是C8051F系列处理器的基本测试程序

;
;为了提高AD，DA性能，T4和ADC0中断使用A51编写
;
$include (c8051f120.inc)

DACOUNTER segment data
	rseg DACOUNTER
count: ds 1;定义计数器0~127

;T4中断代码:
CSEG AT 83H;T4入口地址
jmp start;跳转

T4_ISR segment code
	rseg T4_ISR
start:
push ACC;保存所用到的寄存器值
push 0
push PSW
clr TF3;清T3中断
mov SFRPAGE,#DAC0_PAGE;翻到DAC0页
mov R0,count;读入count，最高位无效
mov A,R0
anl A,#7FH
mov R0,A;读入DAC数值
movx A,@R0
mov DAC0H,A;DAC0H赋值
inc R0
movx A,@R0
mov DAC0L,A
inc R0
mov count,R0;改变count
pop PSW
pop 0
pop ACC
reti

END