Rev. 6.0, 07/02, page 517 of 986
1. Transfer requests are issued simultaneously for channels 0 and 3.
2. Since channel 0 has a higher priority level than channel 3, the channel 0 transfer is executed
first (channel 3 is on transfer standby).
3. A transfer request is issued for channel 1 during the channel 0 transfer (channels 1 and 3 are on
transfer standby).
4. At the end of the channel 0 transfer, channel 0 shifts to the lowest priority level.
5. At this point, channel 1 has a higher priority level than channel 3, so the channel 1 transfer is
started (channel 3 is on transfer standby).
6. At the end of the channel 1 transfer, channel 1 shifts to the lowest priority level.
7. The channel 3 transfer is started.
8. At the end of the channel 3 transfer, the channel 3 and channel 2 priority levels are lowered,
giving channel 3 the lowest priority.
3
1, 3
3
Transfer request
Channel
waiting
DMAC operation
Channel priority
order
1. Issued for channels 0
and 3
3. Issued for channel 1
2. Start of channel 0
transfer
0 > 1 > 2 > 3
1 > 2 > 3 > 0
2 > 3 > 0 > 1
0 > 1 > 2 > 3
4. End of channel 0
transfer
5. Start of channel 1
transfer
6. End of channel 1
transfer
7. Start of channel 3
transfer
8. End of channel 3
transfer
Change of
priority order
Change of
priority order
Change of
priority order
None
Figure 14.4 Example of Changes in Priority Order in Round Robin Mode
Содержание SH7750 series
Страница 106: ...Rev 6 0 07 02 page 56 of 986 ...
Страница 144: ...Rev 6 0 07 02 page 94 of 986 ...
Страница 242: ...Rev 6 0 07 02 page 192 of 986 ...
Страница 270: ...Rev 6 0 07 02 page 220 of 986 ...
Страница 360: ...Rev 6 0 07 02 page 310 of 986 ...
Страница 538: ...Rev 6 0 07 02 page 488 of 986 ...
Страница 706: ...Rev 6 0 07 02 page 656 of 986 ...
Страница 752: ...Rev 6 0 07 02 page 702 of 986 ...
Страница 780: ...Rev 6 0 07 02 page 730 of 986 ...
Страница 822: ...Rev 6 0 07 02 page 772 of 986 ...
Страница 986: ...Rev 6 0 07 02 page 936 of 986 ...
Страница 1030: ...Rev 6 0 07 02 page 980 of 986 ...
Страница 1036: ...Rev 6 0 07 02 page 986 of 986 ...