When the 8088 executes an instruction it performs the specified function Based-Relative Addressing Mode. MOV AH
23 nov. 2019 The instructions is divided into two part the first part is called opcode and the second part is called operand for example MOV AX1234H the ...
17 janv. 2018 Figure 3-1 shows the MOV instruction. ... A segment-to-segment register MOV instruction is the only type of ... MOV AXCX. MOV SP
30 oct. 2019 segment you would use the instruction MOV AX CS:[1234H]. 2. Register Indirect Addressing Mode. This mode is similar to the direct address ...
Le Pentium ne fait pas exception. Il dispose de deux instructions pour empiler et dépiler les données : L'instruction push décrémente le pointeur de pile ESP de
MOV AL -5 ; AX = 000FBh (251). CBW. ; AX = 0FFFBh (-5). RET. CZSOPA unchanged. Clear Carry flag. Algorithm: CF = 0. Page 6 of 53. 8086 instructions
data tableau dw. 50 75
1 janv. 2018 Notice that the MOV instruction cannot transfer data ... The original contents of AX BL
13 oct. 2020 MOV CS AX ; Not allowed (Code segment register is never used as destination). The correct: MOV CX
Data is in the registers specified in the instructions. – eg: MOV AXBX. • Immediate addressing. – Data is a constant and is part of the instruction.
MOV Instruction • Move from source to destination Syntax: MOV destination source • Source and destination have the same size • No more than one memory operand permitted • CS EIP and IP cannot be the destination data count BYTE 100 wVal WORD 2 code mov blcount mov axwVal mov countal mov alwVal ; error mov axcount ; error mov eax
This chapter also discussed multiprecision operations how to perform arithmetic operations using non-arithmetic instructions and how to use arith- metic instructions to perform non-arithmetic operations Arithmetic expressions are much simpler in a high-level language than in assembly language
movInstruction • The mov instruction copies data from one location to another • The following formats are legal for moving data to or from general purpose registers: – mov reg reg – mov mem reg – mov reg mem • The following formats are legal for immediate operands – mov mem immed – mov reg immed • The following format
7) Destination operand of the instruction MOV [BX+DI+6400H] CX 8) Source operand of the instruction MOV AL [BP- 0200H] 9) Destination operand of the instruction MOV [SI] AX 10) Destination operand of the instruction MOV [BX][DI]+0400HAL 11) Source operand of the instruction MOV AX [BP+200H]
There are two very important details to note about the mov instruction First there is no memory to memory move operation The mod-reg-r/m addressing mode byte (see Chapter Four) allows two register operands or a single register and a single memory oper-and There is no form of the mov instruction that allows you to encode two memory addresses
The source can be a register, a memory location, or an immediate number. MOV AX, BX MOV AX, 5000H MOV AX, [SI] MOV AX, [2000H] MOV AX, 50H [BX] MOV [734AH], BX Direct loading of the segment registers with immediate data is not permitted. This instruction pushes the contents of the specified register/memory location on to the stack.
The MOV instruction moves data bytes between the two specified operands. The byte specified by the second operand is copied to the location specified by the first operand. The source data byte is not affected. The MOVX instruction transfers data between the accumulator and external data memory.
The instructionMOV AX, MONEY ;AL dollars, AH cents is now legal. So are the following instructions, which have the sameMOV AL,MOV AH, eff~"t: DOLLARSCENTS Example 10.9 Suppose the following data are declared: .DATAA OW 1234hB LABEL BYTEDW 5678hC LABEL WORDCl CB 9AhC2 DB CBCh
The set of possible operands is the same as for the MOV instruction (Section 4.1.4). Here is a short code example that adds two 32-bit integers: .data var1 DWORD 10000h var2 DWORD 20000h .code mov eax,var1 ; EAX = 10000h add eax,var2 ; EAX = 30000h