JTAG In-Circuit Emulators
In-circuit emulators are used to debug the hardware and software of embedded DSP systems. Requirements dictated by project size, safety and available host system interfaces determine the selection of a suitable emulator.
Current emulators typically use a USB or Ethernet host interface. USB-based emulators require only a few setup and configuration steps, and mostly work USB bus-powered without a dedicated power supply.
Ethernet emulators are more complex to install, but are usable for long distances between the target and host device, and are more reliable in virtual machine environments. Ethernet emulators also avoid ground-loops between DSP-system and PC and prevent coupling PC noise into sensitive circuits.
The galvanic isolation provided by Ethernet however is not adequate for DSP systems operating in high-voltage environments like power inverters or some motor control applications. Such environments call for a dedicated galvanically isolated emulator.
When working on power inverters and AC motor control, the DSP system is often connected to a high voltage potential. To prevent damage in case of malfunction and to fulfill safety requirements, an emulator with galvanic isolation is mandatory. Please check isolation class and the allowable common-mode range.
Embedded Trace Buffer
An embedded trace buffer (ETB) is extremely helpful in debugging algorithms and sporadic failures. ETB allows to play-back and inspect the last executions prior to a trigger event. Most high-end DSPs provide trace buffering. An emulator with trace support is required to make full use of an ETB.
Loading large program files and data arrays is significantly improved by a high JTAG clock. The default is 10 MHz, but some low-cost emulators operate at 1 or 2 MHz only. Many DSPs allow a higher than standard JTAG clock if the board layout is appropriate.
If you want to make use of the extensive data vizualization capabilities provided by the current development tools, check the supported clock speed and preferably select an emulator with an adaptive JTAG clock.
Low-power DSP systems often adapt their IO voltage to save power. Choose your emulator to support the IO voltage range of your target device.
Using an Emulator in a Production Environment
XDS100 emulators are low-cost solutions which are usable with the free Code Composer Studio evaluation license.
XDS200 emulators are characterized by an excellent price-performance ratio.
The XDS510 family also supports older Texas Instruments processors and programming utilities.
High-Performance emulators for extensive debugging.