OpenOCD JTAG server is a open-source on-chip debug solution for targets based on the ARM7, ARM9, Cortex-M3 and XSCALE families with Embedded-ICE macrocell support via JTAG port. It enables source level debugging with the standard GNU Debugger GDB compiled for the ARM architecture. In addition internal and external FLASH memory programming is supported. Any GDB aware integrated development environment, example Eclipse IDE, IAR or Emacs, can benefit from OpenOCD.

OpenOCD PDF User's guide

The most recent version of  OpenOCD User's Guide (PDF)

OpenOCD HTML Documentation

Most recent version of OpenOCD documentation in browsable HTML format.