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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.