AN2168 Freescale Semiconductor / Motorola, AN2168 Datasheet - Page 6

• Manufacturer Part Number: AN2168
• Description: ColdFire Microprocessor DMA Controller Application Note
• Manufacturer: Freescale Semiconductor / Motorola

Application Note
Figure 3
shows the resulting dual address DMA transfer. Since the
DCR[SSIZE] is programmed as word and the chip select mapped to the
source address (CS0) is also a word port size, there is a single read from
the source address. However, the destination size and chip select are
both programmed as bytes. The DMA controller needs to write the full
16 bits of data to the destination, so the read is followed by two byte-size
transfers to the destination address.
Figure 3. Dual Address Transfer, SSIZE = word, DSIZE = byte
AN2168
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