JTAG, also known as IEEE 1149.1, is one of the most successful electronic

standards of all times. JTAG scan chains are a critical piece of nearly every

electronic design. JTAG has become a critical technology for not only

manufacturing testing, but also for development teams. What happens when

you need to see JTAG bus transactions for debug?

While oscilloscopes have long been used to view JTAG signal integrity and

timing issues, the Keysight Technologies, Inc. Infiniium Series is the first scope

family to support JTAG protocol decode.

Extend your scope capability with Keysight’s JTAG decode application. This

application displays real-time time-aligned decode of JTAG (IEEE 1149.1).

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See real-time time-aligned decode of JTAG (IEEE 1149.1) from TDI, TDO,

TMS and TCK signals.

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Quickly describe each unique scan chain and import BSDL files for each

device in the chain

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View JTAG protocol including device names, OPCODES, and flagging of

certain error conditions

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Use time-correlated views to move between protocol and physical layer

views.

JTAG (IEEE 1149.1) Decode Overview

The N8817A application provides real-time, at-speed, JTAG decode from TMS,

TDI, TDO and TCK signals acquired on either scope or digital (MSO) channels.

Signals must be probed at the periphery of the scan chain, and cannot be probed

in the middle of the scan chain.

Easy to find

Turn decode on/off in the “setup” menu. View decode embedded on the

waveform display or in the protocol viewer listing window. (See pages 4-6).

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