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Section 2 CPU
Rev. 4.00 Sep. 14, 2005 Page 29 of 982
REJ09B0023-0400
2.1.1 General
Registers
There are sixteen 32-bit general registers (Rn), designated R0 to R15. The general registers are
used for data processing and address calculation.
With SuperH microcomputer type instructions, R0 is used as an index register. With a number of
instructions, R0 is the only register that can be used.
With DSP type instructions, eight of the sixteen general registers are used for addressing of X and
Y data memory and data memory (single data) that uses the L-bus.
To access X memory, R4 and R5 are used as the X address register [Ax] and R8 is used as the X
index register [Ix]. To access Y memory, R6 and R7 are used as the Y address register [Ay] and
R9 is used as the Y index register [Iy]. To access single data that uses the L-bus, R2, R3, R4, and
R5 are used as the single data address register [As] and R8 is used as the single data index register
[Is].
Figure 2.3 shows the general registers, which are identical to those of the SH3, when DSP
extension is disabled.
31
R0
*
1,
*
2
R1
*
2
R2
*
2
R3
*
2
R4
*
2
R5
*
2
R6
*
2
R7
*
2
R8
R9
R10
R11
R12
R13
R14
R15
0
General Registers (when not in DSP mode)
Notes:
1. R0 functions as an index register in the indexed
register-indirect addressing mode and indexed
GBR-indirect addressing mode. In some
instructions, only R0 can be used as the source
register or destination register.
2. R0 to R7 are banked registers. SR.RB specifies
BANK.
SR.RB = 0; BANK0 is used
SR.RB = 1; BANK1 is used
Figure 2.3 General Registers (Not in DSP Mode)
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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