Question

What is the difference between the following instructions, and identifying their respective addressing modes? A) MOV CX, 437AH and MOV CX, [437AH] B) MOV BL, 437AH and MOV BL, DS:BYTE PTR[437AH]

Answer 1

Explanation: MOV instruction copies a word or byte from a specified source to a specified destination. The destination can be a register or a memory location. The source can be a register or a memory location or an immediate number .

For MOV CX 037AH: put immediate number 037AH to CX

For MOV BL, (437AH) : copy byte in Ds at offset 437AH to BL

For MOV AX BX : copy content register BX to AX

For MOV DL, (BX) : copy byte from memory at(BX) to DL

That identifies the differences. Good luck.