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📝 Read/Write Control Logic in 8085A Microprocessor

📖 From An Introduction To Microprocessor 8085 • 14. Serial Communication and Programmable Communication Interface • 17 questions available

Practice MCQs for Read/Write Control Logic in 8085A Microprocessor. Test your knowledge with carefully crafted questions across easy, medium, and hard difficulty levels.

🔄 Last updated: 2026-07-30

3
Easy Questions
8
Medium Questions
6
Hard Questions

📝 Sample Questions

Q1. What is the maximum number of bytes that can be transferred in a single DMA operation using the 8257 controller?

🔹 A. 8 KB
🔹 B. 16 KB
🔹 C. 32 KB
🔹 D. 64 KB

💡 Difficulty: easy | ✅ Correct: B

Q2. What role does the HRQ (HOLD Request) pin play in coordinating DMA with the CPU?

🔹 A. It signals the CPU to pause and grant bus control
🔹 B. It resets the DMA controller
🔹 C. It acknowledges data receipt
🔹 D. It selects the DMA channel

💡 Difficulty: medium | ✅ Correct: A

Q3. Explain how the combination of AEN (Address Enable) and ADSTB (Address Strobe) pins allows the 8257 to perform address multiplexing on the system bus.

🔹 A. They enable simultaneous data and address transfer
🔹 B. AEN disables address lines while ADSTB provides timing for address latch
🔹 C. AEN provides clock and ADSTB provides reset
🔹 D. They are unrelated signals

💡 Difficulty: hard | ✅ Correct: B

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🔗 Related Topics

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