Floating-Point Intel® FPGA IP User Guide

ID 683750
Date 8/30/2024
Public
Document Table of Contents

3.5. Floating Point Functions IP Reset and Latency

You can pipeline Floating Point Functions IPs to user-specified performance goals by targeting:
  • A specified frequency
  • A specified latency or
  • A combined frequency-latency.

Regardless of the selected performance profile, a number, L, of pipeline stages, are automatically inserted in the generated IPs to meet these performance goals. These L pipeline stages form the latency of the IP. For these IPs to correctly operate, the reset signal must be asserted for at least one clock cycle. One cycle is sufficient to reset any finite state machine (FSM) that the IP may internally create. For instance, you can use such FSMs to replace long register chains (which the IP may use in parallel path balancing) with more efficient memory-based delay chains.

On deasserting reset, the IP requires a total of L clock cycles for the pipeline to flush. The first valid output result (i.e. the result that corresponds to the first set of inputs after the reset is deasserted) are only available after these L cycles. While the IP flushes the pipeline, the bit-pattern returned at the output is undefined.