What's Happening at SEGGER?

2012 |
Jun. 08
J-Link, Press Releases 2012
SWO Monitor for J-Link

Free SWO Monitor for J-Link

SEGGER introduced SWOViewer – a new, free-of-charge utility for the industry leading debug emulator, J-Link. This utility displays the terminal output of the target using the SWO pin.

SWOViewer can be used without a debugger to capture terminal output independently from the debugger. Additionally, it can be run side by side with a debugger which does not support terminal output via SWO, such as GDB or GDB/Eclipse. SWOViewer is part of the latest J-Link software package which can be downloaded free of charge from SEGGER's website. It does not require a license and can be used on any current J-Link model.

“Many customers using GDB and Eclipse, have been asking us for such a tool in order to take advantage of this unique feature of the Cortex-M series CPUs. It also comes in handy when supervising a target outside of the control of the debugger. We believe it adds more value to the J-Link offering for anybody using a Cortex-M family CPU”, says Dirk Akemann, marketing manager of SEGGER.

Behind the Technology

SWO is a dedicated pin of ARM's Cortex-M debug interface. While it can be used to output various information in real time via the CPU, its main use is to handle terminal output in real-time with very low intrusion. This permits most programs to perform debug outputs via terminal without losing their real-time behavior. More information about J-Link SWO Viewer


About J-Link

The SEGGER J-Link is the most popular debug probe on the market. It is tool chain independent and works with free GDB-based tool chains such as emIDE and Eclipse, as well as commercial IDEs from: Microchip (MPLAB® X), Atmel, Atollic, Coocox, Cosmic, Freescale, IAR, KEIL, Mentor Graphics, Python, Rowley, Renesas, Tasking and others. With the J-Link family, investments in the debug probe are preserved when changing compiler or even CPU architecture.

J-Link supports multiple CPU families, such as ARM 7, 9, 11, Cortex-M0, M0+, M1, M3, M4, R4, A5, A8, A9 as well as Renesas RX100, RX200, RX610, 620, 62N, 62T, 630, 631, 63N and Microchip PIC32; there is no need to buy a new J-Link or new license when switching to a different yet supported CPU family or tool-chain. SEGGER is also continuously adding support for additional cores, which in most cases, only requires a software/firmware update. Unlimited free updates are included with even the baseline model of the J-Link family. SEGGER is excited to continue advanced development of its cutting edge embedded tool solutions to be utilized with pretty much any development environment you choose. All J-Links are fully compatible to each other, so an upgrade from a lower-end model to a higher-end model is a matter of a simple plug-and-play.

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