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Program the DMA Controller for Memory Transfers

hard6/8

Implement Serial Port Output with UART 16550 Program VGA Registers for Graphics Modes

Language

Compiler

2.0s Limit 256MB

Submit and pass all tests to enable saving to GitHub.

Implementation

Implement DMA controller programming in C.

Requirements:

Define DMA channel structure
Implement dma_disable_channel(channel)
Implement dma_set_mode(channel, mode)
Implement dma_set_address(channel, phys_addr)
Implement dma_set_count(channel, count)
Implement dma_enable_channel(channel)
Show physical address calculation with page register
Implement a floppy read simulation using DMA
Print DMA register states
Show flip-flop reset

Test:

Show channel disabled
Show mode set
Show address programmed
Show count programmed
Show channel enabled
Show transfer complete

Why This Matters

The Intel 8237's page-register-plus-16-bit-address scheme you compute here (physical = page<<16 | offset) is legacy silicon still wired into every PC motherboard's Super I/O chip purely to keep the floppy controller and LPC bus working, decades after modern storage moved to PCIe bus-mastering DMA. Linux's own drivers/scsi and legacy floppy.c drivers still touch this exact register set on systems that expose it.

Hints

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Validation Suite

main.c

Workspace 1.0

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