SH7764 Datasheet, PDF (192/1752 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC Engine Family SH-4A Series

Section 6 Floating-Point Unit (FPU)
See section 11, Instruction Descriptions of SH-4A Extended Functions Software Manual for
details of floating-point operations when a non-number (NaN) is input.
6.2.3 Denormalized Numbers
For a denormalized number floating-point value, the exponent field is expressed as 0, and the
fraction field as a non-zero value.
When the DN bit in FPSCR of the FPU is 1, a denormalized number (source operand or operation
result) is always positive or negative zero in a floating-point operation that generates a value (an
operation other than transfer instructions between registers, FNEG, or FABS).
When the DN bit in FPSCR is 0, a denormalized number (source operand or operation result) is
processed as it is. See section 11, Instruction Descriptions of SH-4A Extended Functions Software
Manual for details of floating-point operations when a denormalized number is input.
Rev. 1.00 Nov. 22, 2007 Page 136 of 1692
REJ09B0360-0100