微机LC-3_4.中断实验

用户程序

R3-6

NO

RTI

R1--;

R30?

R3-10;

.ORIG x3000

R1-mem[SaveR1];

YES

R6-StackPointer;(初始化栈指针)

PUTS\"\\";

R2--;

R20?

DELAY

START

R1=0?

RET;

R2=0?

.ORIG x2000

Address_KBDR\t.FILL xFE02Address_KBSR\t.FILL xFE00Address_DDR\t.FILL xFE06Address_DSR\t.FILL xFE04LineFeed\t.FILL x000A_LineFeed\t.FILL xFFF6SaveChar\t.BLKW 1SaveR0\t\t.BLKW 1SaveR1\t\t.BLKW 1SaveR2\t\t.BLKW 1SaveR3\t\t.BLKW 1

StackPointer\t.FILL x3000KIVTE .FILL x0180\tInterruptAddr\t.FILL x2000Enable\t.FILL x4000\tAddress_KBDR\t.FILL xFE02Address_KBSR\t.FILL xFE00Address_DDR\t.FILL xFE06Address_DSR\t.FILL xFE04COUNT \t.FILL x8000SaveR1 .BLKW 1Letter_I\t.FILL x0049Letter_C\t.FILL x0043Letter_S\t.FILL x0053Space\t.FILL x0020LineFeed\t.FILL x000A

PUTS\" \";(3个空格符)

中断服务程序

mem[SaveR1]-R1;R1-COUNT;

PUTS\"ICS\";

R2-6

R3--;

R10?