预处理阶乘和阶乘逆元
Problem statement:
问题陈述：
Write an assembly language program for calculating the factorial of a number using 8086 microprocessor.
编写一个汇编语言程序，以使用8086微处理器来计算数字的阶乘。
Assumptions:
假设：
Starting address of program: 0400
程序起始地址：0400
Input memory location: 0500
输入存储器位置：0500
Output memory location: 0600 and 0601
输出存储器位置：0600和0601
Point to be noted:
需要注意的地方：
If the Given Number is a 16-bit number, the AX register is automatically used as the second parameter and the product is stored in the DX:AX register pair. This means that the DX register holds the high part and the AX register holds the low part of a 32-bit number.
如果给定数字是16位数字，则AX寄存器将自动用作第二个参数，并且乘积存储在DX：AX寄存器对中。 这意味着DX寄存器保持32位数字的高位，而AX寄存器保持32位数字的低位。
Algorithm:
算法：
Input the Number whose factorial is to be find and Store that Number in CX Register (Condition for LOOP Instruction)
输入要查找其阶乘的编号，并将该编号存储在CX寄存器中(LOOP指令的条件)
Insert 0001 in AX(Condition for MUL Instruction) and 0000 in DX
在AX(MUL指令的条件)中插入0001，在DX中插入0000
Multiply CX with AX until CX become Zero(0) using LOOP Instruction
使用LOOP指令将CX与AX相乘，直到CX变为零(0)
Copy the content of AX to memory location 0600
将AX的内容复制到内存位置0600
Copy the content of DX to memory location 0601
将DX的内容复制到内存位置0601
Stop Execution
停止执行
Program:
程序：
| ADDRESS | MNEMONICS | COMMENTS |
|---|---|---|
| 0400 | MOV CX, [0500] | CX ← [0500] |
| 0404 | MOV AX, 0001 | AX ← 0001 |
| 0407 | MOV DX, 0000 | DX ← 0000 |
| 040A | MUL CX | DX:AX ← AX * CX |
| 040C | LOOP 040A | Go To [040A] till CX->00 |
| 0410 | MOV [0600], AX | [0600]←AX |
| 0414 | MOV [0601], DX | [0601]←DX |
| 0418 | HLT | Stop Execution |
| 地址 | 记忆 | 注释 |
|---|---|---|
| 0400 | MOV CX，[0500] | CX←[0500] |
| 0404 | MOV斧，0001 | 斧←0001 |
| 0407 | MOV DX，0000 | DX←0000 |
| 040A | MUL CX | DX：AX←AX * CX |
| 040C | 环040A | 转到[040A]直到CX-> 00 |
| 0410 | MOV [0600]，AX | [0600]←AX |
| 0414 | MOV [0601]，DX | [0601]←DX |
| 0418 | HLT | 停止执行 |
Explanation:
说明：
MOV CX, [0500] loads 0500 Memory location content to CX Register
MOV CX ，[0500]将0500内存位置内容加载到CX寄存器
MOV AX, 0001 loads AX register with 0001
MOV AX ，0001将0001装入AX寄存器
MOV DX, 0000 loads DX register with 0000
MOV DX ，0000将0000装入DX寄存器
MUL CX multiply AX with CX and store result in DX:AX pair
MUL CX将AX与CX相乘并将结果存储在DX：AX对中
LOOP 040A runs loop till CX not equal to Zero
LOOP 040A循环运行，直到CX不等于零
MOV [0600], AX store AX register content to memory location 0600
MOV [0600] ，AX将AX寄存器内容存储到内存位置0600
MOV [0601], DX store DX register content to memory location 0601
MOV [0601] ，DX将DX寄存器内容存储到存储器位置0601
HLT stops the execution of program
HLT停止执行程序
翻译自: https://www.includehelp.com/embedded-system/calculate-the-factorial-of-a-number.aspx
预处理阶乘和阶乘逆元
