Why does the Multi-Channel DMA FPGA IP for PCI Express* stall or stop operating when the Q_SIZE parameter is configured to 0x10?
Description Due to a problem in the Quartus® Prime Pro Edition software version 24.2 and later, the Multi-Channel DMA FPGA IP for PCI Express* may stall or cease operation when the Q_SIZE parameter is set to 0x10. Resolution The recommended workaround is to limit Q_SIZE to 0xF. If your design requires a Q_SIZE of 0x10, upgrade to the Quartus® Prime Pro Edition software version 25.3.1, regenerate the Multi-Channel DMA FPGA IP for PCI Express, and recompile the design to ensure the fix takes effect.Why does the Nios® V processor that applies fast JTAG UART driver stop (stuck in a loop) when the JTAG UART terminal is not active?
Description Due to a problem in the Board Support Package Editor of Quartus ® Prime software, the JTAG UART driver for fast implementation might get stuck in a loop for any Nios ® V processor designs, when JTAG UART terminal is not active. This problem has been present since: Quartus ® Prime Pro Edition software version 21.3 Quartus ® Prime Standard Edition software version 22.1 It is because the JTAG UART IP is initialized before the Nios ® V processor initialization in alt_sys_init.c. For example: void alt_sys_init( void ) { ALTERA_AVALON_JTAG_UART_INIT (JTAG_UART, jtag_uart); INTEL_NIOSV_M_INIT (NIOS, nios); } Resolution To work around this problem, update the alt_sys_init.c to initialize the Nios ® V processor first. void alt_sys_init( void ) { INTEL_NIOSV_M_INIT (NIOS, nios); ALTERA_AVALON_JTAG_UART_INIT (JTAG_UART, jtag_uart); } This problem is currently scheduled to be resolved in a future release of the Quartus ® Prime software. Additional Information Refer to Embedded Peripherals IP User Guide [titled as JTAG UART Core - Driver Options: Fast vs. Small Implementations] for more information about the JTAG UART driver for fast (non-blocking) and slow (blocking) implementation. Related Article NIOSV firmware stuck when juart-terminal is not open for the print messages.
Why does the ASMI Parallel II IP or the Generic Quad SPI Controller II IP fail to access a QSPI flash memory device?
Description Due to a problem in multiple Quartus® Prime Pro Edition and Standard Edition software versions, the ASMI Parallel II IP or the Generic Quad SPI Controller II IP fails to access a Quad SPI flash memory device. The affected software versions are: Quartus® Prime Pro Edition software versions from 22.1 to 25.3 Quartus® Prime Standard Edition software versions from 22.1 to 24.1 Chronologically, Prior to version 22.1, the initial state of DATA[3:2] was high. For the affected software versions, the initial state of DATA[3:2] was incorrectly changed to Hi-Z. For reader’s information, some quad SPI flash memory devices support RESET or HOLD function on DATA[3] and WRITE_PROTECT function on DATA[2]. DATA pins can be known as DATA, DQ, IO, or SIO across different QSPI flash memory device vendors. This modification to Hi-Z is recognized as low, thus the active-low RESET, HOLD and WRITE_PROTECT functions are enabled. With these, they prevent the flash controller IP from gaining access to flash devices. Resolution DATA[3:2] must be kept high as the initial state. If the targeted flash device is the Active Serial configuration flash memory, this problem is fixed starting from, Quartus® Prime Pro Edition software version 25.3.1, and Quartus® Prime Standard Edition software version 25.1. Otherwise (i.e. generic-purpose flash memory or affected software version), please refer to the workarounds below. For affected software versions, Targeted Flash Device Workarounds Active Serial configuration flash memory Differentiated with: DATA[3:2] pins are assigned to dedicated AS_DATA[3:2] pins Disable dedicated Active Serial interface option is turned off The initial state of DATA[3:2] is Hi-Z. Add external pull-up registers to the I/O VCC voltage on DATA[3:2]. Internal weak pull-up resistor option is unavailable for dedicated AS_DATA pins. Generic-purpose flash memory Differentiated with: DATA[3:2] pins are assigned to generic I/O pins Disable dedicated Active Serial interface option is turned on The initial state of DATA[3:2] is Hi-Z. Add external pull-up registers to the I/O VCC voltage on DATA[3:2], or Enable internal weak pull-up resistor on DATA[3:2] pins in Quartus® design project After Quartus® Prime Pro Edition software version 25.3.1 and Quartus® Prime Standard Edition software version 25.1, Targeted Flash Device Workarounds Active Serial configuration flash memory Differentiated with: DATA[3:2] pins are assigned to dedicated AS_DATA[3:2] pins Disable dedicated Active Serial interface option is turned off The initial state of DATA[3:2] is reverted to high. No workaround is needed. Generic-purpose flash memory Differentiated with: DATA[3:2] pins are assigned to generic I/O pins Disable dedicated Active Serial interface option is turned on The initial state of DATA[3:2] is Hi-Z. Add external pull-up registers to the I/O VCC voltage on DATA[3:2], or Enable internal weak pull-up resistor on DATA[3:2] pins in Quartus® design project Related IP Cores ASMI Parallel II IP, Generic Quad SPI Controller II IPWarning(332174): Ignored filter at alt_sld_fab_0_st_dc_fifo_<unique ID>.sdc(Line number): *|in_wr_ptr_gray[*] could not be matched with a register
Description Due to a problem in the Quartus® Prime Pro Edition Software version 25.3, you might see 'ignored filter' SDC warnings when your design includes the Partial Reconfiguration External Configuration Controller IP. Resolution This warning is safe to ignore and is scheduled to be removed in a future release of the Quartus® Prime Pro Edition Software. Related IP Core Partial Reconfiguration External Configuration Controller IPWhy does Ashling* RiscFree* IDE for Altera® FPGAs detect Core 0 only in a Nios® V processor multicore system?
Description Due to a problem in the Ashling* RiscFree* IDE for Altera software version 25.2.1 (version dated 9 th May 2025), the Ashling* RiscFree* IDE might fail to detect other Nios ® V processor cores (except Core 0) for Nios ® V processor multicore designs. This is because there is a bug in the Ashling* GDBServer software. Error message: [GDB server output] Error: The device configuration selected has only 1 core (Core 0). Core 1 is not available. Resolution To workaround this issue, please switch from Ashling* GDBServer to Open On-Chip Debugger (OpenOCD) when debugging a Nios ® V multicore processor system. Add the “–o" argument when running niosv-download. niosv-download app.elf -o <options> This problem is scheduled to be fixed, beginning with the Ashling* RiscFree* IDE for Altera software version 25.3.1 (version dated 1 st August 2025).Why does Quartus® Prime Pro Edition Installer for software version 25.3 install an older version of Ashling* RiscFree* IDE for Altera® (version dated 31st Jan 2025)?
Description Due to a problem in the Quartus ® Prime Pro Edition Installer for software version 25.3, it installs an older version of Ashling* RiscFree* IDE for Altera ® software. For example: Quartus ® Prime Pro Edition software version 25.1 is paired with Ashling* RiscFree* IDE for Altera ® v25.1.1 (dated as 31 st Jan 2025). Quartus ® Prime Pro Edition software version 25.1.1 is paired with Ashling* RiscFree* IDE for Altera ® v25.2.1 (dated as 9 th May 2025). However, Quartus ® Prime Pro Edition software version 25.3 is paired with Ashling* RiscFree* IDE for Altera ® v25.1.1 (dated as 31 st Jan 2025). Thus, an older Ashling* RiscFree* IDE for Altera software is installed. This is because the installer is incorrectly packaged with the older software. Resolution To work around this problem in the Quartus ® Prime Pro Edition software version 25.3, please download the Ashling* RiscFree* IDE for Altera ® v25.2.1 (dated as 9 th May 2025) separately from the Quartus ® Prime Pro Edition Installer for software version 25.1.1. And use it with the Quartus ® Prime Pro Edition software version 25.3 for your project. You may follow these steps: Go to the Quartus® Prime Pro Edition Installer for software version 25.1.1 download link. Select the appropriate Operating System. Download the Quartus® Prime Pro Edition Installer. Launch the installation. Select the following files to install: Add-ons and Standalone Software > Ashling* RiscFree* IDE for Altera Add-ons and Standalone Software > Quartus ® Prime Pro Edition Programmer and ToolsWhy does Ashling* RiscFree* IDE for Altera® FPGAs fail to debug a Nios® V processor C++ software project in Windows?
Description Due to a problem with the Ashling* RiscFree* IDE for Altera ® FPGAs software, debugging a Nios ® V processor software project may fail when it is written in the C++ language. This is because there is a bug in the processor toolchain from the Ashling* RiscFree* IDE for Altera ® FPGAs software. C projects are not affected by this issue. You might receive the following error messages. Error Messages How is RISC-V GDB executed? Error in services launch sequence: GDB prompt not read From Ashling* RiscFree* IDE for Altera software ../../../gdb/gdb/cp-name-parser.y:192: internal-error: fill_comp: Assertion ‘i’ failed. Executing riscv32-unknown-elf-gdb commands in the command-line interface The affected Ashling* RiscFree* IDE for Altera ® FPGAs software versions are: 24.3.1 (version dated 9 th Aug 2024) 24.4.0 (version dated 27 th Sep 2024) 25.1.1 (version dated 31 st Jan 2025) Note that: This problem only affects Windows environments. C projects are not affected by this problem. Resolution This problem is fixed beginning with the Ashling* RiscFree* IDE for Altera ® FPGAs software version 25.2.1 (version dated 9 th May 2025). You can download Ashling* RiscFree* IDE for Altera ® FPGAs software version 25.2.1 (version dated 9 th May 2025) separately from Quartus® Prime Pro Edition Installer for software version 25.1.1. Follow these steps: Go to the Quartus® Prime Pro Edition Installer for software version 25.1.1 download link. Select Windows as the Operating System. Download the Quartus® Prime Pro Edition Installer for software version 25.1.1. Launch the installation. Select the following files to install: Add-ons and Standalone Software > Ashling* RiscFree* IDE for Altera Add-ons and Standalone Software > Quartus ® Prime Pro Edition Programmer and Tools Note: Refrain from using the Quartus® Prime Pro Edition Installer for software version 25.3 to resolve this problem. The installer contains the older version of the Ashling* software (Software version 25.1.1).Why do I see a large timing violation when using the IOPLL IP’s Non-Dedicated Feedback Path option?
Description A timing violation may occur when the Non-Dedicated Feedback Path option is enabled in the IOPLL IP. This is caused by the C-counter starting to toggle unexpectedly, resulting in a phase shift of the output clocks relative to the input clock. This problem affects the following device families: Stratix® 10 FPGAs Agilex™ 3 FPGAs Agilex™ 5 FPGAs Agilex™ 7 FPGAs Resolution To address this timing violation, add multi-cycle constraints to the impacted timing paths. 1) The set_multicycle_path constraint should only be applied to the affected path. 2) The affected clock domain can be either the source or the destination clock domain in the timing transfers that this behavior may impact.Error: niosv_g_dcache.sv: part-select direction is opposite from prefix index direction
Description Due to a problem in the: Quartus® Prime Pro Edition Software version 24.3.1, 25.1, and Quartus® Prime Standard Edition Software version 24.1 When the Nios® V/g processor is configured with No Data Cache and enabled with Error Detection and ECC Status Reporting, performing Analysis and Synthesis fails with the error "niosv_g_dcache.sv: part-select direction is opposite from prefix index direction". Note that this issue has no relationship with No Instruction Cache. Figure. Nios® V/g Processor Setting to Replicate the Error Resolution To work around this error, Select 1Kbytes Data Cache. Apply a Peripheral Region that covers the whole Nios® V processor’s data_manager address map Enable Error Detection and ECC Status Reporting. By implementing Peripheral Region, the above settings can emulate an ECC-enabled Nios® V processor system that operates without caches. Figure. Workaround (in this example, the whole Nios® V processor’s data_manager address map is 1GB) This problem is scheduled to be fixed in a future release of the Quartus® Prime Edition Software.Why doesn't the Triple-Speed Ethernet (TSE) FPGA IP for all devices always maintain a negative running disparity during idle cycles as per the IEEE 802.3 standard?
Description Due to a problem in the Quartus® Prime Pro Edition software, when using the Triple-Speed Ethernet (TSE) FPGA IP across supported device families, the transmitter may not maintain a negative running disparity during idle cycles as defined in the IEEE 802.3 standard. Specifically, the first IDLE sequence after a packet or configuration set is not always generated as /I1/, which is required to restore the running disparity to negative. Resolution A patch is available to fix this problem for the Quartus® Prime Pro Edition software version 24.1 for Agilex™ 7 FPGA F-Series E-Tile devices. Download version 24.1 patch 0.47 for Windows and Linux below This patch ensures the transmitter maintains negative running disparity for Agilex™ 7 FPGA F-Series E-Tile devices by inserting the first idle sequence (/I1/) whenever required, followed by all subsequent idle sequences (/I2/), maintaining compliance with the IEEE 802.3 standard. Please contact your local Sales representative or submit a request through the Support page for further support. This problem is scheduled to be fixed in a future release of the Quartus Prime Pro Edition software.
