Hardware JTAG Testing
During the development and manufacturing process of JTAG enabled computer chips and modules, the JTAG port is commonly used to validate and test the new hardware. DebugJet has an extensive built-in JTAG testing capabilities to support such features for development and manufacturing purposes.
DebugJet target server application supports macro language that allow the user to execute JTAG scan functions, such as SCAN IR/DR, and take full control of the JTAG bus behavior using a script language based on the Serial Vector Format (SVF) language. The target server application also allows the user to execute native SVF and STAPL test files and provide the test results to the user.
To develop a test application, the user has to write a simple macro script file to be executed by the DebugJet target server application. The first instructions are normally used to set the JTAG port speed and possibly the position of the chip under test if the JTAG bus has multiple chips cascaded together. The following instructions are normally used to initiate scan functions to execute the test. The results for the scan functions are output by the application for the user review.
A second application that comes with DebugJet, the JTAG tester application, is capable of executing standard JTAG scan functions to test JTAG chips during development process and offers two ways for achieving such a task. The first is to simply enter the values in a binary format and then execute the desires scan function. The application will execute the function and display the results on the screen. Additionally the application allows the user to execute native SVF and STAPL test files.
DebugJet JTAG tester application is more suitable for allowing the user to run simple one-time tests during hardware development. While this utility allows the user to simply enter the desired parameters directly in the application, the target server application allows the user to write a script macro file to be executed over and over for multiple modules. This can be used to test the new hardware modules during a manufacturing process.
The JTAG scan functions can be also called and executed from the Xpresso debugger to test for a special conditions or execute custom JTAG scans. This is very useful if the user is debugging a hardware module that is connected to the CPU under debug via a JTAG port. It also enables the user to have more flexibility when debugging custom hardware that does not confirm to the standard JTAG hardware offered by DebugJet processor driver.
Available software libraries allow any custom software to directly access and control the JTAG port for more customized JTAG testing. Please contact EmuTec for more info.
Supports Serial Vector Format (SVF) test files.
Full Support for STAPL language for JTAG based hardware testing.
Full featured Macro script language enabling the user to execute JTAG tests in development and manufacturing environment.
JTAG scanning and testing can be done from within the Xpresso debugger during a debug session to support custom hardware debugging.
Software libraries are available to support custom software applications under Windows and Linux.
DebugJet JTAG Tester software is available for free download from the support section.