Hitachi SH7751 Hardware Manual page 180

(8) Unconditional Trap


Source: Execution of TRAPA instruction


Transition address: VBR + H'0000 0100


Transition operations:
As this is a processing-completion-type exception, the PC contents for the instruction
following the TRAPA instruction are saved in SPC. The value of SR and R15 when the
TRAPA instruction is executed are saved in SSR and SGR. The 8-bit immediate value in the
TRAPA instruction is multiplied by 4, and the result is set in TRA [9:0]. Exception code H'160
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.
TRAPA_exception()
{
SPC = PC + 2;
SSR = SR;
SGR = R15;
TRA = imm << 2;
EXPEVT = H'00000160;
SR.MD = 1;
SR.RB = 1;
SR.BL = 1;
PC = VBR + H'00000100;
}
Rev. 3.0, 04/02, page 141 of 1064