Renesas SH7781 User Manual

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5. Exception Handling

Rev.1.00 Jan. 10, 2008 Page 117 of 1658

REJ09B0261-0100

(12)

Slot FPU Disable Exception

• Source: Decoding of an FPU instruction in a delay slot with SR.FD =1
• Transition address: VBR + H'00000100
• Transition operations:

The PC contents for the preceding delayed branch instruction are saved in SPC. The SR and
R15 contents when this exception occurred are saved in SSR and SGR.

Exception code H'820 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.

Slot_fpu_disable_exception()

{

SPC = PC - 2;

SSR = SR;

SGR = R15;

EXPEVT = H'0000 0820;

SR.MD = 1;

SR.RB = 1;

SR.BL = 1;

PC = VBR + H'0000 0100;

}