Variable Precision DSP Blocks User Guide: Agilex™ 5 FPGAs and SoCs

ID 813968
Date 9/20/2024
Public
Document Table of Contents

3.2.1.3. Multiply Accumulate Mode

This mode performs floating-point multiplication followed by floating-point addition or subtraction with the previous multiplication result.

When ACCUMULATE signal is high, this mode uses the equation of fp32_result(t) = [fp32_mult_a(t)*fp32_mult_b(t)] +/- fp32_result(t-1).

When ACCUMULATE signal is low, this mode uses the equation of fp32_result = fp32_mult_a*fp32_mult_b.

The floating-point multiply accumulate mode supports the following exception flags:
  • fp32_mult_invalid
  • fp32_mult_inexact
  • fp32_mult_overflow
  • fp32_mult_underflow
  • fp32_adder_invalid
  • fp32_adder_inexact
  • fp32_adder_overflow
  • fp32_adder_underflow
Figure 35. Multiply Accumulate Mode for Agilex™ 5 Devices