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Section 2 CPU
Page 52 of 2108 R01UH0134EJ0400 Rev. 4.00
Sep 24, 2014
SH7262 Group, SH7264 Group
2.1.3 System Registers
The system registers consist of four 32-bit registers: the high and low multiply and accumulate
registers (MACH and MACL), the procedure register (PR), and the program counter (PC). MACH
and MACL store the results of multiply or multiply and accumulate operations. PR stores the
return address from a subroutine procedure. PC points four bytes ahead of the current instruction
and controls the flow of the processing.
31 0
31 0
31
PC
PR
MACL
MACH
Multiply and accumulate register high (MACH) and multiply
and accumulate register low (MACL):
Store the results of multiply or multiply and accumulate operations.
Procedure register (PR):
Stores the return address from a subroutine procedure.
Program counter (PC):
Indicates the four bytes ahead of the current instruction.
0
Figure 2.3 System Registers
(1) Multiply and Accumulate Register High (MACH) and Multiply and Accumulate
Register Low (MACL)
MACH and MACL are used as the addition value in a MAC instruction, and store the result of a
MAC or MUL instruction.
(2) Procedure Register (PR)
PR stores the return address of a subroutine call using a BSR, BSRF, or JSR instruction, and is
referenced by a subroutine return instruction (RTS).
(3) Program Counter (PC)
PC points four bytes ahead of the instruction being executed.