Flasher PRO

SEGGER’s Flasher PRO is an in-system programming (ISP) tool used to program non-volatile memory, soldered onto a PCB. ISP is also known as ICP or in-circuit programming.

The memories that can be programmed range from the internal flash memory of microcontrollers and SoCs to external parallel flash memory (CFI Flashes) as well as (Q)SPI flashes. (Q)SPI flashes can also be programmed by connecting directly to the pins.

It is fast, robust, reliable, and engineered to handle almost all flash programming requirements in the industry. The Flasher PRO can be used in stand-alone or PC-based mode. It connects via USB, Ethernet or an RS232 interface.

Powered via USB, the Flasher PRO has 128 MB of internal memory to store firmware images and programming configurations. The 20-pin target connector adapts to multiple standard and proprietary connectors through a wide variety of adapters from SEGGER. The Flasher PRO supports a large number of CPU cores and an even greater number of different devices from various vendors.

As a multi-platform solution, Flasher PRO comes with the setup and control software for Linux, macOS and Windows.

Key features

  • High speed
  • Large number of devices supported
  • Flexible programming interface: Almost anything can be programmed.
  • Multiple status and control options
  • Reliability
  • Longevity
  • Multi-platform: Includes setup and control software for Linux, macOS, and Windows.
  • No license required. No hidden costs. No future costs.
  • Future proof: Software, firmware updates, and new flash loaders are free of charge.

Supported devices

SEGGER Flashers support a wide range of CPU cores and an even wider range of different devices, such as SPI-Flash devices.

This includes support for tens of thousands of devices in hundreds of device families with billions of devices programmed.

Universal target support

Flasher PRO has a very flexible target and programming interface.

Based on an FPGA with an integrated CPU core, it has multiple dedicated soft cores controlling the target interface, and a virtual processor running the flash loader.

This concept makes it possible to adapt to almost any system for ISP programming purposes. Dedicated flash loaders, which can be easily downloaded to the programmer, make it possible to program almost any device. This flexibility allows using the debug or dedicated programming interfaces of microcontrollers to program the on-chip memories as well as the programming of the off-chip parallel or (Q)SPI flashes. (Q)SPI can also be programmed directly.


Future software and firmware updates as well as any new flash loaders for target devices that will be added, are also free of charge.

  • No licensing cost, even for newly supported devices.
  • No hidden costs.
  • No future costs.


As a multi-platform solution, Flasher PRO comes with the setup and control software for Linux, macOS and Windows. Software and firmware updates are included. Similarly, use on all currently supported target devices, and any that will be added, is also included.

High-speed programming

Flasher programmers are designed to achieve top programming speeds, coming very close to the theoretical minimum programming time of the target hardware. In many cases, more than 95 % of the maximum speed can be achieved, often resulting in a programming speed of more than 1 MB /  s.

Turbo mode

For microcontrollers which are programmed via debug interface and which allow memory access while the CPU is running, Flasher is able to minimize overhead by simultaneously downloading and programming. This “turbo mode” makes it possible to reach speeds not achievable by other programmers.

Flexible control and monitoring

The Flasher PRO is easy to set up and operate using SEGGER software tools. It can be operated in either stand-alone or PC-based programming mode. In stand-alone mode it can be operated via remote control (USB, UART, Ethernet) or by the push of a button or TTL triggers.

Serial number assignment

Many modern devices require some pieces of unique information. Flasher PRO allows the programming of data that differs amongst other otherwise identical units. Typical examples are things like serial numbers, ethernet hardware addresses (MAC), and digital signatures, and license keys that enable/disable product features. All these options can be adapted from device to device by applying patch data to the original firmware.

Built-in web server

The Flasher PRO offers options to check status information remotely and to configure the device.

Remote monitoring

The Flasher PRO comes with SEGGER’s built-in web server. It is designed to present important device and current operation data for a quick overview and, additionally, to check the status of the programmer, providing information about:

  • Installed firmware version
  • Hardware version
  • Power consumption
  • IP configuration
  • Network load
  • Current operation and status
  • Programming interface in use

This may be important for fast troubleshooting through code verification, for instance, as it is when executing a cyclic redundancy check (CRC) that helps to detect errors during data transmission or storage.

Flasher Pro Network Configuration


If needed, the built-in web server’s programmer settings can be checked and adjusted. These could, for example, be parameters like:

  • Nickname
  • Subnet mask
  • Gateway
Flasher Pro Status

Built-in FTP server

The Flasher PRO also includes the emFTP server to upload firmware and configuration or download log files.

Remote file update

Using the emFTP server enables easy upload of configuration files and firmware images. By connecting to the emFTP server using an FTP client of choice, files can be transferred between client and Flasher.

Having access to the Flasher configuration via FTP enables configuration of multiple Flashers from a central production control server. This interface can be also used to make the production line part of a CI/CD system to push stable releases into the current production.

Flasher Pro Remote File Update

Log file

Analyzing the reliability of the production line is an important task, when it comes to increasing the production frequency. This purpose is supported by the built-in FTP server, which lets users check the history of past programming cycles via log file download. Each entry provides the following information:

  • Result (success/failure)
  • Duration
  • Serial number (if programmed)
Flasher Pro Log File

For failed programming cycles, the log file provides additional information for quick troubleshooting (e.g. failed to open Flasher config file).

Use cases

Maximum line speed for lean manufacturing

The SEGGER Flasher PRO is built to maximize programming speed for single or multiple programming lines within production environments. Using (Q)SPI, Flasher PRO minimizes programming times thus maximizing the number of devices that can be programmed in a given amount of time. In terms of speed, the Flasher PRO comes close to the theoretical minimum programming time for the target hardware.

  • Maximum speed
  • Reliable programming
Flasher Pro Max Line Speed

Different hardware platforms in production environments

In production environments, different hardware platforms often have to be programmed with different firmware images. With the universal Flasher PRO, these different platforms can be programmed with one device. With multiple file support it is also possible to have multiple data files and config files on the Flasher PRO. It is even possible to program multiple targets which are located in a JTAG chain. The targets will be programmed each with an individual configuration and a data file.

Flasher PRO XL — The universal flash programmer for huge images

Flasher Pro XL

The Flasher PRO XL is the extra-large memory version of SEGGER’s Flasher PRO. With all the same features of the Flasher PRO, the XL expands upon the original’s 128 MB memory with 2 gigabytes—16 times as much as the internal flash memory. This memory can be used to store large a variety of large program images.

Technical specifications


Power supplyUSB powered, 500  mA if target is powered by Flasher PRO
USB host interfaceUSB 2.0 (High-Speed), USB Type B
RS232 host interfaceRS232 9-pin
Target interfaceJTAG 20-pin (14-pin adapter available)
Max. target cable lengthRecommended (delivered): 20 cm (8″)
Max. 2 m (6.5″) allowed but might reduce max. target interface speed.
Serial transfer rate between Flasher PRO and targetMax. target interface (JTAG, …) speed: 50 MHz
Supported target voltage1.2 – 5 V
Current drawn from target voltage sense pin (VTRef)< 25 µA
Target supply voltage5 V
Target supply currentMax. 400 mA
Operating temperature5 °C … + 60 °C
Storage temperature20 °C … + 65 °C
Relative humidity (non-condensing)< 90 % rH
Size (without cables)121 mm x 66 mm x 30 mm
Weight (without cables)120 g
Supported OSMicrosoft Windows (x86/x64), Linux (x86/x64/Arm), macOS (x86/Apple Silicon)

Package content

flasher pro
USB Cable
20Pin Target Ribbon
RS232 Cable

Flasher PRO

USB cable

20-pin, 0.1″ target ribbon cable

RS232 cable 1:1 female / male