Term · Embedded Software & Tools
JTAG chain
Several JTAG-capable devices wired in series on one debug connector, each with its own instruction register length, so tools must know the chain order and lengths to address a specific device.
Scanning it is the first step in board bring-up.
- Also known as
- Daisy chain, Scan chain
- Type
- Term
- Domain
- Embedded Software & Tools, Debug and trace
Notes
A chain that scans as all ones or all zeros usually means a power, reset or TDO wiring problem rather than a dead die.
Related terms
Part of the Embedded Software & Tools glossary, with every term in the topic and the lifecycles, tools and standards that use them.
Where it appears on the Hub
Used on 2 pages of the Hub. In each group, the pages that mention it most come first.
Lifecycle stages and gates
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Last reviewed: not yet reviewed in depth. Entry last updated . The full glossary