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	WHAT'S YOUR ENGINEERING QUOTIENT?
Problem 6—Write the assembly code to set all the 8086 flags to '1' at one go without using any arithmetic or logical instructions. Answer: We normally use instructions like STD/CLD (set/clear direction flag), STI/CLI (set/clear interrupts) and so forth to modify individual control flags. But the conditional flags are modified only indirectly as a result of arithmetic or logical operations. However, it is possible to set/reset individual flags or all the flags at one go using the following code: MOV AX, 0FFFFh PUSH AX POPF AX is filled with ones and pushed onto the stack. Then it is popped into the flags register, which sets all of the flags to '1'. To set individual bits of the flags register, just fill AX with the appropriate value and push it onto the stack. Contributor: Naveen P N 5-01 — NEXT Q&A For questions or comments about Test Your EQ, e-mail eq@circuitcellar.com.