When Bus Grant (BG) = 1 in direct memory access (DMA) transfer, then what function read line and write lines perform?
ARead line and write line act as input line allowing CPU to communicate with internal DMA register
BRead line act as input line and write line act as output line from DMA
CRead line act as output line and write line act as input line from DMA controller
DRead line and write line act as output lines from DMA controller
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Correct answer: (D) Read line and write line act as output lines from DMA controller
Explanation
When BG = 1 the CPU has given up the buses and the DMA controller is the bus master, so its RD and WR lines become outputs that control memory reads and writes.
From DSSSB PGT Computer Science PYQ (Technical), 11 Jul 2021