JTAG Boundary Scan Testing and Programming Tools

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JTAG Boundary Scan Testing, JTAG Device Programming and JTAG Debug

XJTAG provides high-end, professional hardware and software boundary scan products to speed up circuit design and development, through to production test and field maintenance. We can offer you a full range of JTAG products to help you debug board designs with BGAs, test hardware that includes FPGAs, CPLDs, DSPs or microprocessors, detect faults and prove your design quickly and easily. Free Trial » More about the XJTAG tools »

XJTAG/XJAnalyser Demo Watch video »	XJDeveloper Demo Watch video »	XJRunner Demo Watch video »
What's new in XJTAG 2.6? Watch video » new	Basic Pin Mapping tutorial Watch video »	Advanced Pin Mapping Watch video »

JTAG Overview

JTAG is a test access protocol built into most high pin count BGA devices and many smaller devices too. It is also referred to as Boundary Scan.
The JTAG-enabled devices in your circuit are connected to form a JTAG Chain, accessed via a 4-signal header on your board.
JTAG is a set of IEEE standards (1149.x), so you can chain together JTAG devices from any manufacturer including Xilinx, Texas Instruments, Altera, NXP, etc.
JTAG software tools connected to your board give test access to hundreds or thousands of circuit nodes, without lifting a 'scope probe!

JTAG and Board Testing

JTAG can locate assembly defects on circuit boards. To do this JTAG controlled pins drive test patterns on to the PCB nets. These are carefully designed to reveal any 'opens' or 'shorts'.

JTAG software tools such as XJDeveloper check each board against its PCB net list and BSDL (Boundary Scan Description Language) files for the JTAG devices. BSDL files define the mapping between the JTAG Chain and the balls/pins of JTAG devices.

Testing using JTAG is non-contact and non-invasive: JTAG is normally the only way to test the soldering integrity of Ball Grid Array (BGA) and Chip Scale Package (CSP) parts.

JTAG and Application Processors

The JTAG interface also combines a debug and emulation port for most application processor and system-on-chip (SoC) cores such as ARM, MIPS, PowerPC and x86. XJDeveloper can access and program resources like on-chip Flash. Low-level debug commands can also be integrated into the board test suite.

JTAG and Device Programming

Most CPLDs and FPGAs use JTAG for In-System Programming (ISP) and for Boundary Scan. Assembled parts from many manufacturers including Xilinx, Altera, Lattice and Cypress can be programmed and tested via the JTAG Test Access Port (TAP).

Flash parts can be programmed indirectly via a JTAG device. If the JTAG device is a FPGA, XJFlash firmware can perform ultra-fast program/verify.

A JTAG test system such as XJDeveloper can merge 'test' and 'program' into one manufacturing step, and it can be run on low cost XJRunner production units.

More about JTAG

If your products rely on Processors, FPGAs, CPLDs or BGA parts, XJTAG tools can reduce your costs and improve reliability. This web site gives you most of the information you need, but the best way to see what you can achieve is through a demonstration or evaluation at your own site.

Contact an XJTAG representative today or take a FREE trial, or better still take advantage of XJTAG's free board setup program.