SH7263 Datasheet, PDF (126/1862 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7260 Series

Section 3 Floating-Point Unit (FPU)
3.2.3 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.
In the SH2A-FPU, the DN bit in the status register FPSCR is always set to 1, therefore a
denormalized number (source operand or operation result) is always flushed to 0 in a floating-
point operation that generates a value (an operation other than copy, 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 the individual instruction descriptions for details of floating-point
operations when a denormalized number is input.
Rev. 2.00 Mar. 14, 2008 Page 92 of 1824
REJ09B0290-0200