📝 Programmable Communication Interface IC 8251 in 8085A Microprocessor

Q1. If a CPU loads the DMA Address Register with \(0x2000\) and the Terminal Count Register with \(0x3FFF\), how many bytes will be transferred before the DMA channel stops?

💡 Difficulty: easy | ✅ Correct: B

Q2. What is the maximum number of bytes that a single DMA operation can transfer using the 8257?

💡 Difficulty: medium | ✅ Correct: D

Q3. Two peripherals, a printer and a disk controller, simultaneously assert DRQ0 and DRQ2 while the CPU issues a HOLD request. Which of the following best describes the sequence of events?

💡 Difficulty: hard | ✅ Correct: A