SH7760 Datasheet, PDF (100/1345 Pages) Renesas Technology Corp – SuperHTM RISC engine

The FPU exception cause field in FPSCR contains bits corresponding to all of above sources E, V,
Z, O, U, and I, and the FPU exception flag and enable fields in FPSCR contain bits corresponding
to sources V, Z, O, U, and I, but not E. Thus, FPU errors cannot be disabled.
When an FPU exception occurs, the corresponding bit in the FPU exception cause field is set to 1,
and 1 is added to the corresponding bit in the FPU exception flag field. When an FPU exception
does not occur, the corresponding bit in the FPU exception cause field is cleared to 0, but the
corresponding bit in the FPU exception flag field remains unchanged.
3.5.3 FPU Exception Handling
FPU exception handling is initiated in the following cases:
• FPU error (E): FPSCR.DN = 0 and a denormalized number is input
• Invalid operation (V): FPSCR.Enable.V = 1 and (instruction = FTRV or invalid operation)
• Division by zero (Z): FPSCR.Enable.Z = 1 and division with a zero divisor
• Overflow (O): FPSCR.Enable.O = 1 and instruction with possibility of operation result
overflow
• Underflow (U): FPSCR.Enable.U = 1 and instruction with possibility of operation result
underflow
• Inexact exception (I): FPSCR.Enable.I = 1 and instruction with possibility of inexact operation
result
Rev. 1.0, 02/03, page 50 of 1294