
Section 12 Bus State Controller (BSC)
Rev. 4.00 Sep. 14, 2005 Page 355 of 982
REJ09B0023-0400
Burst Write: A burst write occurs in the following cases in this LSI.
•
Access size in writing is larger than data bus width.
•
Write-back of the cache
•
16-byte transfer in DMAC
This LSI always accesses SDRAM with burst length 1. For example, write access of burst length 1
is performed continuously 4 times to write 16-byte continuous data to the SDRAM that is
connected to a 32-bit data bus.
The relationship between the access size and the number of bursts is shown in table 12.14.
Figure 12.21 shows a timing chart for burst writes. In burst write, an ACTV command is output in
the Tr cycle, the WRIT command is issued in the Tc1, Tc2, and Tc3 cycles, and the WRITA
command is issued to execute an auto-precharge in the Tc4 cycle. In the write cycle, the write data
is output simultaneously with the write command. After the write command with the auto-
precharge is output, the Trw1 cycle that waits for the auto-precharge initiation is followed by the
Tap cycle that waits for completion of the auto-precharge induced by the WRITA command in the
SDRAM. Between the Trwl and the Tap cycle, a new command will not be issued to the same
bank. However, access to another CS space or another bank in the same SDRAM space is enabled.
The number of Trw1 cycles is specified by the TRWL1 and TRWL0 bits in the CS3WCR register.
The number of Tap cycles is specified by the WTRP1 and WTRP0 bits in the CS3WCR register.
Содержание HD6417641
Страница 2: ...Rev 4 00 Sep 14 2005 Page ii of l...
Страница 7: ...Rev 4 00 Sep 14 2005 Page vii of l...
Страница 11: ...Rev 4 00 Sep 14 2005 Page xi of l USB Universal serial bus WDT Watch dog timer...
Страница 12: ...Rev 4 00 Sep 14 2005 Page xii of l...
Страница 28: ...Rev 4 00 Sep 14 2005 Page xxviii of l...
Страница 204: ...Section 4 Clock Pulse Generator CPG Rev 4 00 Sep 14 2005 Page 154 of 982 REJ09B0023 0400...
Страница 212: ...Section 5 Watchdog Timer WDT Rev 4 00 Sep 14 2005 Page 162 of 982 REJ09B0023 0400...
Страница 228: ...Section 6 Power Down Modes Rev 4 00 Sep 14 2005 Page 178 of 982 REJ09B0023 0400...
Страница 246: ...Section 8 X Y Memory Rev 4 00 Sep 14 2005 Page 196 of 982 REJ09B0023 0400...
Страница 318: ...Section 11 User Break Controller UBC Rev 4 00 Sep 14 2005 Page 268 of 982 REJ09B0023 0400...
Страница 454: ...Section 12 Bus State Controller BSC Rev 4 00 Sep 14 2005 Page 404 of 982 REJ09B0023 0400...
Страница 500: ...Section 13 Direct Memory Access Controller DMAC Rev 4 00 Sep 14 2005 Page 450 of 982 REJ09B0023 0400...
Страница 504: ...Section 14 U Memory Rev 4 00 Sep 14 2005 Page 454 of 982 REJ09B0023 0400...
Страница 566: ...Section 17 Compare Match Timer CMT Rev 4 00 Sep 14 2005 Page 516 of 982 REJ09B0023 0400...
Страница 734: ...Section 18 Multi Function Timer Pulse Unit MTU Rev 4 00 Sep 14 2005 Page 684 of 982 REJ09B0023 0400...
Страница 868: ...Section 21 A D Converter Rev 4 00 Sep 14 2005 Page 818 of 982 REJ09B0023 0400...
Страница 914: ...Section 23 I O Ports Rev 4 00 Sep 14 2005 Page 864 of 982 REJ09B0023 0400...
Страница 956: ...Section 24 List of Registers Rev 4 00 Sep 14 2005 Page 906 of 982 REJ09B0023 0400...
Страница 1016: ...Section 25 Electrical Characteristics Rev 4 00 Sep 14 2005 Page 966 of 982 REJ09B0023 0400...
Страница 1024: ...Appendix Rev 4 00 Sep 14 2005 Page 974 of 982 REJ09B0023 0400...
Страница 1032: ...Rev 4 00 Sep 14 2005 Page 982 of 982 REJ09B0023 0400 X X Y data addressing 52 X Y memory 193...
Страница 1035: ......
Страница 1036: ...SH7641 Hardware Manual...