IAR's Workbench now shows power usage linked to code
IAR captures power information via the JTAG interface
IAR Systems combines its program trace tool with voltage capture via is JTAG probe. This allows real time tracing of both the application and the power consumed by the system. Essentially it delivers basic logic analyzer features in one compact package.
IAR Systems demonstrated its IAR Embedded Workbench working with one of its Cortex-M3 development kits at the 2010 Embedded Systems Conference in San Jose. ARM's Cortex-M3 JTAG interface allows real time tracing of the program counter. IAR's JTAG interface also captures the current operating voltage and records that along with the program counter in its trace log.
The IAR Embedded Workbench provides a real time display. It also allows developers to set thresholds so there are color changes in the display. In one instance, the IAR representative was able to highlight overvoltage in red. Displaying the matching code is as simple as double clicking the red bar.
Trace results are already used to find bugs such as deadlock and race conditions. The addition of power information allows developers to detect hot spots in power usage as well as determine where optimum low power code is working properly.
In the future, expect to be able to set breakpoints based on power consumption. This will allow tricks like stopping or flaggin an application that consumes too much power in some routine when the system is in a particular state. The ability to save the trace results could allow more sophisticated power analysis.