3. Read 4 bytes from 0x2000_0004, increment SARn, write 4 bytes.
4. Repeat 4-byte operations until SARn equals 0x2000_00F0.
5. Read byte from 0x2000_00F0, increment SARn, write byte.
If DSIZE is another size, data writes are optimized to write the largest size allowed based
on the address, but not exceeding the configured size.
23.4.5 Termination
An unsuccessful transfer can terminate for one of the following reasons:
• Error conditions—When the DMA encounters a read or write cycle that terminates
with an error condition, DSRn[BES] is set for a read and DSRn[BED] is set for a
write before the transfer is halted. If the error occurred in a write cycle, data in the
internal holding registers is lost.
• Interrupts—If DCRn[EINT] is set, the DMA drives the appropriate interrupt request
signal. The processor can read DSRn to determine whether the transfer terminated
successfully or with an error. DSRn[DONE] is then written with a one to clear the
interrupt, the DONE, and error status bits.
Chapter 23 DMA Controller Module
KL25 Sub-Family Reference Manual, Rev. 3, September 2012
Freescale Semiconductor, Inc. 365
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