Why do I see intermittent device recovery failures with error code 0x3ff in ASx4 configuration mode with HPS? - Why do I see intermittent device recovery failures with error code 0x3ff in ASx4 configuration mode with HPS? Description When configuring Agilex™ 5 or Agilex™ 3 SoC FPGAs in Active Serial x4 (ASx4) mode, intermittent device recovery failures with error code 0x3ff may occur if the mailbox interface is under heavy usage from the Hard Processor System (HPS). This issue is more likely to happen when nCONFIG is toggled multiple times in quick succession, particularly under stress or repeated reconfiguration scenarios. Resolution To minimize the chance of this error: Reduce mailbox traffic from the HPS during configuration and reconfiguration. If error 0x3ff occurs, reassert nCONFIG and attempt to reconfigure the device. In rare cases, if the error persists, a full power cycle of the device may be required to restore normal operation. This problem is scheduled to be fixed in a future release of the Quartus® Prime Pro Software. For more details on configuration modes refer to the Device Configuration User Guide: Agilex™ 5 FPGAs and SoCs or Device Configuration User Guide: Agilex™ 3 FPGAs and SoCs , for error handling refer to Agilex™ 5 Hard Processor System Technical Reference Manual or Agilex™ 3 Hard Processor System Technical Reference Manual . Custom Fields values: ['novalue'] Troubleshooting 16027842059 True ['novalue'] ['FPGA Dev Tools Quartus® Prime Software Pro'] novalue 25.1.1 ['Agilex™ 5 FPGAs and SoCs'] ['novalue'] ['novalue'] ['novalue']