MC68HC708XL36 FREESCALE [Freescale Semiconductor, Inc], MC68HC708XL36 Datasheet - Page 113

• Manufacturer Part Number: MC68HC708XL36
• Description: HCMOS Microcontroller Unit
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

Functional Description
3-dma_b
MOTOROLA
The DMA is a coprocessor for servicing peripheral devices that require
data block transfers. For transmitting or receiving blocks of data to or
from peripherals, DMA transfers are faster and more code-efficient than
CPU interrupts. The following tasks that contribute to CPU interrupt
overhead are not part of a DMA transfer:
Once the DMA is initialized to transfer a block of data, a DMA service
request usually requires only two bus cycles per 8-bit byte or four cycles
per 16-bit word to transfer the source data to a destination.
Figure 1
transfer data independently between any addresses in the memory map.
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Freescale Semiconductor, Inc.
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Stacking and unstacking CPU registers
Loading interrupt vectors
Loading address pointers
Incrementing address pointers
Storing address pointers
Clearing interrupt flags
Returning from interrupt
shows the structure of the DMA. Each DMA channel can
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DMA
Functional Description
MC68HC708XL36
DMA
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