r8a77850anbg Renesas Electronics Corporation., r8a77850anbg Datasheet - Page 33

• Manufacturer Part Number: r8a77850anbg
• Description: Renesas 32-bit Risc Microcomputer Superh? Risc Engine Family
• Manufacturer: Renesas Electronics Corporation.

Item
FPU
Features
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On-chip floating-point coprocessor
Supports single (32-bit) and double (64-bit) precisions
Supports IEEE754-compliant data types and exceptions
Two rounding modes: Round to Nearest and Round to Zero
Handling of denormalized numbers: Truncation to zero or interrupt-
generation for IEEE754 compliance
Floating-point registers: 32 bits × 16 words × 2 banks
(single-precision × 16 words or double-precision × 8 words) × 2 banks
32-bit CPU-FPU floating-point communications register (FPUL)
Supports FMAC (multiply-and-accumulate) instruction
Supports FDIV (divide) and FSQRT (square root) instructions
Supports FLDI0/FLDI1 (load constants 0 and 1) instructions
Instruction-execution times
⎯ Latency (FADD/FSUB): 3 cycles (single-precision), 5 cycles (double-
⎯ Latency (FMAC/ FMUL): 5 cycles (single-precision), 7 cycles (double-
⎯ Pitch (FADD/FSUB): 1 cycle (single-precision/double-precision)
⎯ Pitch (FMAC/FMUL): 1 cycle (single-precision), 3 cycles (double-
3-D graphics instructions (single-precision only)
⎯ 4-dimensional vector-conversion and matrix operations (FTRV):
⎯ 4-dimensional vector (FIPR) inner product: 1 cycle (pitch), 5 cycles
Ten-stage pipeline
precision)
precision)
precision)
4 cycles (pitch), 8 cycles (latency)
(latency)
FMAC only supports single-precision operands.
Rev.1.00 Jan. 10, 2008 Page 3 of 1658
REJ09B0261-0100
1. Overview