Cyclone V SoC Power Optimization

ID 683713
Date 2/09/2015
Document Table of Contents HPS Method 3: CPU1 in WFI/WFE or Standby Loop

On boot, CPU1 is held in reset. If you do not intend to make use of the CPU1, you should put it into a Standby Loop in order to benefit from around 90 mW of power savings.

  1. Place the following code for CPU1 at a known address in on-chip memory:
    Note: The code is GCC specific. Similar syntax can be used with other compliers.
  2. Configure this address in the cpu1startaddr register in the system manager.
  3. Pull CPU1 out of reset (the default) using the cpu1 register in the reset manager.