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  • About J-Flash

    J-Flash
    Program internal & external microcontroller flash

    J-Flash is a PC software running on Microsoft Windows systems, Linux or macOS, which enables you to program the internal and external flash of your microcontroller via J-Link or Flasher.

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    Documentation
    SEGGER Debug & Trace Probes
    1. 1.Licensing
    2. 2.System requirements
    3. 3.Performance Values
      1. 3.1.Programming Speeds on Internal Flash
      2. 3.2.Programming Speeds on QSPI NOR Flash
    4. 4.What is Multi-Bank Programming support?
    5. 5.Memory mapped QSPI flash support
    6. 6.SPI flash support
    7. 7.eMMC support
    8. 8.DataFlash support
    9. 9.NAND flash support

    Overview

    J-Flash comes with sample projects for most popular microcontrollers and evaluation boards which run out-of-the-box.

    J-Flash can be controlled via GUI or via command line which makes it also possible to use J-Flash for production purposes.

    Key features

    • Supports most Cortex A-R-M, RX and Power PC devices/cores
    • Supports the following internal and external flash devices:
    • Internal flash of most popular microcontrollers
    • CFI-compliant NOR flash (the combinations 1x8, 2x8, 1x16, 2x16 are supported)
    • Most non-CFI compliant NOR flash devices (the combinations 1x8, 2x8, 1x16, 2x16 are supported)
    • SPI NOR-flash
    • NAND flash

    Licensing

    For all J-Trace and J-Link models higher than J-Link BASE, J-Flash is included in the J-Link Software and Documentation Package, which can be downloaded here:

    DownloadJ-Link Software and Documentation Pack

    J-Link BASE requires an upgrade BASE to PLUS, which is available in our  web shop.

    System requirements

    Supported OS
    WindowsMicrosoft Windows (x86/x64)
    macOSmacOS (x86/Apple Silicon)
    LinuxLinux (x86/x64/Arm)

    Performance Values

    Information on the performance values can be found in the tables below. Device series, program and program verification are indicated in the tables. They provide an illustration of example values with frequently used devices. This demonstrates the write performance for flash memory of J-Flash and J-Link.

    Programming Speeds on Internal Flash

    Device SeriesProgramProgram and Verify
    Cypress CYT2B98CAC_M0988 KB / s938 KB / s
    NXP LPC1857431 KB / s431 KB / s
    Renesas R7FA6M3AH398 KB / s388 KB / s
    Renesas R7FS5D97E396 KB / s395 KB / s
    ST STM32H735IGK364 KB / s358 KB / s

    Programming Speeds on QSPI NOR Flash

    Device SeriesQSPI FlashProgramProgram and Verify
    NXP MIMXRT595Macronix MX25UW51345G1086 KB / s1086 KB / s
    NXP MIMXRT685SMacronix MX25UM51345G988 KB / s988 KB / s
    NXP MIMXRT1052ISSI IS25WP064A865 KB / s486 KB / s
    NXP MIMXRT1064 internal QSPIWinbond W25Q32JV390 KB / s386 KB / s
    NXP MK80FN256V15Macronix MX25U3235F362 KB / s323 KB / s
    Renesas R7FA6M3AHMacronix MX25L25645G954 KB / s797 KB / s
    Renesas R7FS5D97EWinbond W25Q64FV439 KB / s442 KB / s
    ST STM32H757XI QSPIMT25QL512ABB8ESF1080 KB / s959 KB / s
    ST STM32L4R9AI QSPIMacronix MX25LM51245G964 KB / s763 KB / s
    ST STM32L562QE QSPIMacronix MX25LM51245G1043 KB / s894 KB / s

    What is Multi-Bank Programming support?

    Multi-bank programming support describes the possibility to program different flash devices, present on the same hardware, in one Flash programming session. For example, if you want to use the internal flash of your target hardware as well as the external flash for the target application code, multi-bank programming enables you to download the target application into the internal and external flash in one flash programming session. The settings for both flash banks are saved in the same J-Flash project, so you will only need one project in order to program multiple flash banks.

    Memory mapped QSPI flash support

    Most modern MCUs have a dedicated QSPI unit on-chip that makes the QSPI flash memory mapped available in the MCU address space so that it can access the QSPI flash like parallel flash and directly execute instructions from it (execute-in-place, XiP). For most of such MCUs, QSPI flash programming is supported out-of-the-box. If it is supported for a specific MCU, please refer to the list of supported devices.

    SPI flash support

    As SPI flash memories are not memory-mapped and can be connected to basically any SPI unit a MCU provides, there are no out-of-the-box algorithms available for that. However, customers can always add a flash bank and algorithm on their own for supporting such flashes by making use of the open flash loader functionality. For more information, please refer to the SEGGER Knowledge Base.

    eMMC support

    There are no out-of-the-box algorithms available for that. However, customers can always add a flash bank and algorithm on their own for supporting such flashes by making use of the open flash loader functionality. For more information, please refer to the SEGGER Knowledge Base.

    DataFlash support

    As DataFlash memories are not memory-mapped and can be connected to basically any SPI unit a MCU provides, there are no out-of-the-box algorithms available for that. However, customers can always add a flash bank and algorithm on their own for supporting such flashes by making use of the open flash loader functionality. For more information, please refer to the SEGGER Knowledge Base.

    NAND flash support

    As NAND flash memories are not memory-mapped and can be connected in different ways to the MCU (dedicated NAND flash controller, just GPIOs, ...), there are no out-of-the-box algorithms available for that. However, customers can always add a flash bank and algorithm on their own for supporting such flashes by making use of the open flash loader functionality. For more information, please refer to the SEGGER Knowledge Base.

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