Access port selector for access port and compliant access port

Patent metadata

Field	Value
Publication number	US-8990649-B2
Application number	US-201313891840-A
Country	US
Kind code	B2
Filing date	May 10, 2013
Priority date	Sep 14, 2009
Publication date	Mar 24, 2015
Grant date	Mar 24, 2015

Abstract

The disclosure describes a novel method and apparatuses for allowing a controller to select and access different types of access ports in a device. The selecting and accessing of the access ports is achieved using only the dedicated TDI, TMS, TCK, and TDO signal terminals of the device. The selecting and accessing of device access ports can be achieved when a single device is connected to the controller, when multiple devices are placed in a daisy-chain arrangement and connected to the controller, or when multiple devices are placed in a addressable parallel arrangement and connected to the controller. Additional embodiments are also provided and described in the disclosure.

First claim

What is claimed is:

1. An integrated circuit comprising:
A. a TDI input lead, TMS input lead, TCK input lead, and TDO output lead;
B. a first access port having an input connected to the TDI input lead, an input connected to the TMS input lead, an input connected to the TCK input lead, an enable input, and a data output coupled to the TDO output lead, the first test access port including a data register, a bypass register, and an instruction register having inputs coupled to the…

Assignees

• Texas Instruments Inc

Inventors

• Whetsel Lee D

Classifications

• G01R31/31723

  Physics · mapped topic

• G01R31/318533 Primary

  Physics · mapped topic

• G01R31/31725

  Physics · mapped topic

• G01R31/3177 Primary

  Physics · mapped topic

• G01R31/31727

  Physics · mapped topic