Free SWO Monitor for J-Link

Hilden, Germany - October 4th, 2012 – 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. 

The SEGGER J-Link is the industry-standard for ARM debug emulators, supported by all major tool chains for ARM cores. The SEGGER J-Link is independent and will work with IDEs from: Freescale, IAR, KEIL, Mentor Graphics, Rowley, Renesas, Tasking, Phyton and others.

About J-Link

In addition to those listed above; any RDI compliant debugger can be used with the optional RDI module, and any GDB compliant debugger with the free GDB-Server. Therefore; as projects change, a different compiler/debugger may have to be used. With the J-Link family, investments (monetary and learning curve) in development/production tools are preserved.  

Setup of a J-Link is done in mere minutes. J-Link supports multiple CPU families, such as ARM 7, 9, 11, Cortex-M0, M1, M3, M4, R4, A5, A8, A9, Renesas RX in a single model; there is typically no need to buy a new J-Link or new license when switching to a different 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. 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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