无效有效地址计算

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请看看下面的程序，错误是无效的有效地址计算，我已经提到，行，请告诉我，为什么它的无效有效地址计算这里是节目结果

[组织的0x100]JMP启动数组1：DW 10,15,20,25,30,35,40,45,50,55数组2：DW 15,10,20,35,40,30,55,50,25,45启动：MOV BX，0    MOV CX，0循环：MOV AX，[数组2 + BX]        CMP AX，[数组1 + CX] //这里是错误无效的有效地址计算        JNE NextElementOfArray1NextElementOfArray2：加BX，2                        CMP BX，20            JE结束                        MOV CX，0            JMP环NextElementOfArray1：加CX，2                        CMP CX，20            JE NextElementOfArray2            JMP环结束：MOV AX，0x4c00    INT为0x21

解决方案

启动：MOV BX，0        MOV DX，0; ＆LT; - 你的意思是MOV CX，0？循环：MOV AX，[数组2 + BX]        CMP AX，[数组1 + CX]

编辑：如果我没有记错， CX 寄存器不能用作指数

表2-1。 16位寻址与MODR / M字节形式

有效地址模r MODR / M字节的/ M值（十六进制）[BX + SI][BX + DI][BP + SI][BP + DI][SI][二][BX][BX + SI] + disp8[BX + DI] + disp8[BP + SI] + disp8[BP + DI] + disp8[SI] + disp8[二] + disp8[BP] + disp8[BX] + disp8[BX + SI] + disp16[BX + DI] + disp16[BP + SI] + disp16[BP + DI] + disp16[SI] + disp16[二] + disp16[BP] + disp16[BX] + disp16

Please look at the following program, the error is invalid effective address calculation and i have mentioned that line please tell me why its invalid effective address calculation here is the program

[org 0x100] jmp start array1: dw 10,15,20,25,30,35,40,45,50,55 array2: dw 15,10,20,35,40,30,55,50,25,45 start: mov bx,0 mov cx,0 loop: mov ax,[array2+bx] cmp ax,[array1+cx]//here is the error invalid effective address calculation jne NextElementOfArray1 NextElementOfArray2: add bx,2 cmp bx,20 je end mov cx,0 jmp loop NextElementOfArray1: add cx,2 cmp cx,20 je NextElementOfArray2 jmp loop end: mov ax,0x4c00 int 0x21

解决方案

start: mov bx,0 mov dx,0 ; <-- did you mean "mov cx, 0" ? loop: mov ax,[array2+bx] cmp ax,[array1+cx]

Edit: If I recall correctly, cx register can not be used as an index.

Table 2-1. 16-Bit Addressing Forms with the ModR/M Byte

Effective Address Mod R/M Value of ModR/M Byte (in Hexadecimal) [BX+SI] [BX+DI] [BP+SI] [BP+DI] [SI] [DI] [BX] [BX+SI]+disp8 [BX+DI]+disp8 [BP+SI]+disp8 [BP+DI]+disp8 [SI]+disp8 [DI]+disp8 [BP]+disp8 [BX]+disp8 [BX+SI]+disp16 [BX+DI]+disp16 [BP+SI]+disp16 [BP+DI]+disp16 [SI]+disp16 [DI]+disp16 [BP]+disp16 [BX]+disp16