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Section 13 Direct Memory Access Controller (DMAC)
Rev. 4.00 Sep. 14, 2005 Page 436 of 982
REJ09B0023-0400
Figure 13.8 shows example of DMA transfer timing in single address mode.
Address output to external memory space
Select signal to external memory space
Select signal to external memory space
Data output from external device with
DACK
DACK
signal (active-low) to external device with
DACK
Write strobe signal to external memory space
Address output to external memory space
Data output from external memory space
DACK
signal (active-low) to external device with
DACK
Read strobe signal to external memory space
(a) External device with
DACK
→
external memory space (ordinary memory)
(b) External memory space (ordinary memory)
→
external device with
DACK
CK
A25 to A0
D31 to D0
DACKn
CSn
WE
CK
A25 to A0
D31 to D0
DACKn
CSn
RD
Figure 13.8 Example of DMA Transfer Timing in Single Address Mode
Bus Modes: There are two bus modes: cycle steal and burst. Select the mode in the TB bits of the
channel control register (CHCR).
1. Cycle-Steal Mode
•
Normal mode
In the normal mode of cycle-steal, the bus mastership is given to another bus master after a
one-transfer-unit (byte, word, longword, or 16 bytes unit) DMA transfer. When another
transfer request occurs, the bus masterships are obtained from the other bus master and a
transfer is performed for one transfer unit. When that transfer ends, the bus mastership is
passed to the other bus master. This is repeated until the transfer end conditions are satisfied.
In the cycle-steal mode, transfer areas are not affected regardless of settings of the transfer
request source, transfer source, and transfer destination.
Summary of Contents for HD6417641
Page 2: ...Rev 4 00 Sep 14 2005 Page ii of l...
Page 7: ...Rev 4 00 Sep 14 2005 Page vii of l...
Page 11: ...Rev 4 00 Sep 14 2005 Page xi of l USB Universal serial bus WDT Watch dog timer...
Page 12: ...Rev 4 00 Sep 14 2005 Page xii of l...
Page 28: ...Rev 4 00 Sep 14 2005 Page xxviii of l...
Page 204: ...Section 4 Clock Pulse Generator CPG Rev 4 00 Sep 14 2005 Page 154 of 982 REJ09B0023 0400...
Page 212: ...Section 5 Watchdog Timer WDT Rev 4 00 Sep 14 2005 Page 162 of 982 REJ09B0023 0400...
Page 228: ...Section 6 Power Down Modes Rev 4 00 Sep 14 2005 Page 178 of 982 REJ09B0023 0400...
Page 246: ...Section 8 X Y Memory Rev 4 00 Sep 14 2005 Page 196 of 982 REJ09B0023 0400...
Page 318: ...Section 11 User Break Controller UBC Rev 4 00 Sep 14 2005 Page 268 of 982 REJ09B0023 0400...
Page 454: ...Section 12 Bus State Controller BSC Rev 4 00 Sep 14 2005 Page 404 of 982 REJ09B0023 0400...
Page 504: ...Section 14 U Memory Rev 4 00 Sep 14 2005 Page 454 of 982 REJ09B0023 0400...
Page 566: ...Section 17 Compare Match Timer CMT Rev 4 00 Sep 14 2005 Page 516 of 982 REJ09B0023 0400...
Page 868: ...Section 21 A D Converter Rev 4 00 Sep 14 2005 Page 818 of 982 REJ09B0023 0400...
Page 914: ...Section 23 I O Ports Rev 4 00 Sep 14 2005 Page 864 of 982 REJ09B0023 0400...
Page 956: ...Section 24 List of Registers Rev 4 00 Sep 14 2005 Page 906 of 982 REJ09B0023 0400...
Page 1016: ...Section 25 Electrical Characteristics Rev 4 00 Sep 14 2005 Page 966 of 982 REJ09B0023 0400...
Page 1024: ...Appendix Rev 4 00 Sep 14 2005 Page 974 of 982 REJ09B0023 0400...
Page 1032: ...Rev 4 00 Sep 14 2005 Page 982 of 982 REJ09B0023 0400 X X Y data addressing 52 X Y memory 193...
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