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Section 14 U Memory
Rev. 4.00 Sep. 14, 2005 Page 451 of 982
REJ09B0023-0400
Section 14 U Memory
This LSI has on-chip U memory. It can be used by the CPU, DSP, and DMAC to store instructions
or data.
14.1 Features
The U memory features are listed in table 14.1.
Table 14.1 U Memory Specifications
Parameter Features
Addressing method
Mapping is possible in space P0 or P2
Ports
2 independent read/write ports
•
8-/16-/32-bit access from the CPU (via L bus or I bus)
•
16-/32-bit access from the DSP (via L bus or I bus)
•
8-/16-32-bit access from the CPU (via I bus)
Size 128
kbytes
The U memory resides in addresses H
'
055F0000 to H
'
0560FFFF in space P0 or addresses
H
'
A55F0000 to H
'
A560FFFF (128 kbytes) in space P2. The U memory is divided into page 0 and
page 1 according to the addresses. The U memory can be accessed from the L bus and I bus.
In the event of simultaneous accesses to the same address from different buses, the priority order
is : I bus > L bus. Since this kind of conflict tends to lower U memory accessibility, it is advisable
to provide software measures to prevent such conflict as far as possible. For example, conflict will
not arise if different memory or different pages are accessed by each bus.
U memory is accessed by the CPU or DSP from space P0 via the I bus, a conflict with the DMAC
may occur on the I bus. Since this kind of conflict also tends to lower U memory accessibility, it is
advisable to provide software measures to prevent such conflict as far as possible. For example,
conflict on the I bus can be prevented by using space P2 when the U memory is accessed by the
CPU or DSP.
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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