Renesas SH7781 User Manual

Page 141

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5. Exception Handling

Rev.1.00 Jan. 10, 2008 Page 111 of 1658

REJ09B0261-0100

• Transition operations:

The virtual address (32 bits) at which this exception occurred is set in TEA, and the
corresponding virtual page number (22 bits) is set in PTEH [31:10]. ASID in PTEH indicates
the ASID when this exception occurred.

The PC and SR contents for the instruction at which this exception occurred are saved in SPC
and SSR. The R15 contents at this time are saved in SGR.

Exception code H'0E0 (for a read access) or H'100 (for a write access) is set in EXPEVT. The
BL, MD, and RB bits are set to 1 in SR, and a branch is made to PC = VBR + H'0100. For
details, see section 7, Memory Management Unit (MMU).

Data_address_error()

{

TEA = EXCEPTION_ADDRESS;

PTEH.VPN = PAGE_NUMBER;

SPC = PC;

SSR = SR;

SGR = R15;

EXPEVT = read_access? H'0000 00E0: H'0000 0100;

SR.MD = 1;

SR.RB = 1;

SR.BL = 1;

PC = VBR + H'0000 0100;

}