NXP Semiconductors Kinetis KE1xZ256, Reference Manual

Page: 257 / 1325

8. The channel retires
→
one iteration of the major loop. The eDMA goes idle or
services the next channel.
9. Second hardware, that is, eDMA peripheral, requests channel service.
10. The channel is selected by arbitration for servicing.
11. eDMA engine writes: TCDn_CSR[DONE] = 0, TCDn_CSR[START] = 0,
TCDn_CSR[ACTIVE] = 1.
12. eDMA engine reads: channel TCD data from local memory to internal register file.
13. The source to destination transfers are executed as follows:
a. Read byte from location 0x1010, read byte from location 0x1011, read byte from
0x1012, read byte from 0x1013.
b. Write 32-bits to location 0x2010
→
first iteration of the minor loop.
c. Read byte from location 0x1014, read byte from location 0x1015, read byte from
0x1016, read byte from 0x1017.
d. Write 32-bits to location 0x2014 → second iteration of the minor loop.
e. Read byte from location 0x1018, read byte from location 0x1019, read byte from
0x101A, read byte from 0x101B.
f. Write 32-bits to location 0x2018
→
third iteration of the minor loop.
g. Read byte from location 0x101C, read byte from location 0x101D, read byte
from 0x101E, read byte from 0x101F.
h. Write 32-bits to location 0x201C
→
last iteration of the minor loop
→
major loop
complete.
14. eDMA engine writes: TCDn_SADDR = 0x1000, TCDn_DADDR = 0x2000,
TCDn_CITER = 2 (TCDn_BITER).
15. eDMA engine writes: TCDn_CSR[ACTIVE] = 0, TCDn_CSR[DONE] = 1, INT[n] =
1.
16. The channel retires
→
major loop complete. The eDMA goes idle or services the next
channel.
Chapter 13 Enhanced Direct Memory Access (eDMA)
Kinetis KE1xZ256 Sub-Family Reference Manual, Rev. 3, 07/2018
NXP Semiconductors 257