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Section 2 CPU
Rev. 4.00 Sep. 14, 2005 Page 35 of 982
REJ09B0023-0400
2.1.3 System
Registers
This LSI has four system registers, MACL, MACH, PR and PC (figure 2.6).
MACH
MACL
31
0
PR
31
0
PC
31
0
Multiply and accumulate high and low registers
(MACH and MACL)
Store the results of multiplicationand accumulation
operations.
Procedure register (PR)
Stores the subroutine procedure return address.
Program counter (PC)
Indicates the start address of the current instruction.
Figure 2.6 System Registers
The DSR, A0, X0, X1, Y0 and Y1 registers are also treated as system registers. Therefore,
instructions for data transfer between general registers and system registers are supported for these
registers.
2.1.4 DSP
Registers
This LSI has eight data registers and one control register as DSP registers (figure 2.7). The data
registers are 32-bit width with the exception of registers A0 and A1. Registers A0 and A1 include
8 guard bits (fields A0G and A1G), giving them a total width of 40 bits.
Three kinds of operation access the DSP data registers. The first is DSP data processing. When a
DSP fixed-point data operation uses A0 or A1 as the source register, it uses the guard bits (bits 39
to 32). When it uses A0 or A1 as the destination register, guard bits 39 to 32 are valid. When a
DSP fixed-point data operation uses a DSP register other than A0 or A1 as the source register, it
sign-extends the source value to bits 39 to 32. When it uses one of these registers as the
destination register, bits 39 to 32 of the result are discarded.
The second kind of operation is an X or Y data transfer operation, "MOVX.W" or "MOVY.W".
This operation accesses the X and Y memories through the 16-bit X and Y data buses (figure 2.8).
The register to be loaded or stored by this operation always comprises the upper 16 bits (bits 31 to
16). X0 or X1 can be the destination of an X memory load and Y0 or Y1 can be the destination of
a Y memory load, but no other register can be the destination register in this operation.
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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