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Section 13 Direct Memory Access Controller (DMAC)
Rev. 4.00 Sep. 14, 2005 Page 447 of 982
REJ09B0023-0400
•
Idle cycles between read-read cycles in the same spaces (IWRRS = 01 or more)
•
External wait mask specification (WM = 0).
In addition to the above conditions, the following conditions are included depending on the
detection method of DREQ.
•
For DREQ level detection: only write access
•
For DREQ edge detection: both write access and read access
Phenomenon: The detection timings of the DREQ pin in the above access are shown in figures
13.19 to 13.22.
CKIO
CPU
DMAC write or read
Bus cycle
Non-sensitive period
1st acceptance
2nd acceptance
3rd acceptance possible
Non-sensitive period
DREQ
(Rising edge)
DACK
(High-active)
Figure 13.19 Example of DREQ Input Detection in Cycle Steal Mode Edge Detection
When DACK is Divided to 4 by Idle Cycles
CPU
DMAC write or read
Non-sensitive period
1st acceptance
2nd acceptance
3rd acceptance is after the
next DACK assertion
Non-sensitive period
CKIO
Bus cycle
DREQ
(Rising edge)
DACK
(High-active)
Figure 13.20 Example of DREQ Input Detection in Cycle Steal Mode Edge Detection
When DACK is Divided to 2 by Idle Cycles
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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