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12. DDR2-SDRAM Interface (DBSC2)
Rev.1.00 Jan. 10, 2008 Page 489 of 1658
REJ09B0261-0100
Bit Bit
Name
Initial
Value R/W
Description
23 to 20
⎯
All 0
R
Reserved
These bits are always read as 0. The write value should
always be 0.
Operation when a value other than 0 is written is not
guaranteed.
19 to 16 TRAS3 to
TRAS0
0011
R/W
tRAS (ACT-PRE period) Setting Bits
These bits set the ACT-PRE minimum period constraint
for the same bank. These bits should be set according
to the DDR2-SDRAM specifications. The number of
cycles is the number of DDR clock cycles.
0000: Setting prohibit (If specified, correct operation
cannot be guaranteed.)
:
0010: Setting prohibit (If specified, correct operation
cannot be guaranteed.)
0011: 4 cycles
0100: 5 cycles
:
1110: 15 cycles
1111: Setting prohibit (If specified, correct operation
cannot be guaranteed.)
15
⎯
0 R
Reserved
This bit is always read as 0. The write value should
always be 0.
Operation when a value other than 0 is written is not
guaranteed.
Содержание SH7781
Страница 4: ...Rev 1 00 Jan 10 2008 Page iv of xxx REJ09B0261 0100 ...
Страница 74: ...2 Programming Model Rev 1 00 Jan 10 2008 Page 44 of 1658 REJ09B0261 0100 ...
Страница 272: ...8 Caches Rev 1 00 Jan 10 2008 Page 242 of 1658 REJ09B0261 0100 ...
Страница 376: ...10 Interrupt Controller INTC Rev 1 00 Jan 10 2008 Page 346 of 1658 REJ09B0261 0100 ...
Страница 694: ...13 PCI Controller PCIC Rev 1 00 Jan 10 2008 Page 664 of 1658 REJ09B0261 0100 ...
Страница 762: ...14 Direct Memory Access Controller DMAC Rev 1 00 Jan 10 2008 Page 732 of 1658 REJ09B0261 0100 ...
Страница 788: ...15 Clock Pulse Generator CPG Rev 1 00 Jan 10 2008 Page 758 of 1658 REJ09B0261 0100 ...
Страница 828: ...17 Power Down Mode Rev 1 00 Jan 10 2008 Page 798 of 1658 REJ09B0261 0100 ...
Страница 846: ...18 Timer Unit TMU Rev 1 00 Jan 10 2008 Page 816 of 1658 REJ09B0261 0100 ...
Страница 1292: ...24 Multimedia Card Interface MMCIF Rev 1 00 Jan 10 2008 Page 1262 of 1658 REJ09B0261 0100 ...
Страница 1326: ...25 Audio Codec Interface HAC Rev 1 00 Jan 10 2008 Page 1296 of 1658 REJ09B0261 0100 ...
Страница 1482: ...28 General Purpose I O Ports GPIO Rev 1 00 Jan 10 2008 Page 1452 of 1658 REJ09B0261 0100 ...
Страница 1538: ...30 User Debugging Interface H UDI Rev 1 00 Jan 10 2008 Page 1508 of 1658 REJ09B0261 0100 ...
Страница 1688: ...Appendix Rev 1 00 Jan 10 2008 Page 1658 of 1658 REJ09B0261 0100 ...
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Страница 1692: ...SH7785 Hardware Manual ...