Bi-directional TCK lead carrying TCK and frame data in/out signal

Patent metadata

Field	Value
Publication number	US-9494643-B2
Application number	US-201514822301-A
Country	US
Kind code	B2
Filing date	Aug 10, 2015
Priority date	Jan 5, 2004
Publication date	Nov 15, 2016
Grant date	Nov 15, 2016

Abstract

The present disclosure describes using the JTAG Tap's TMS and/or TCK terminals as general purpose serial Input/Output (I/O) Manchester coded communication terminals. The Tap's TMS and/or TCK terminal can be used as a serial I/O communication channel between; (1) an IC and an external controller, (2) between a first and second IC, or (3) between a first and second core circuit within an IC. The use of the TMS and/or TCK terminal as serial I/O channels, as described, does not effect the standardized operation of the JTAG Tap, since the TMS and/or TCK I/O operations occur while the Tap is placed in a non-active steady state.

First claim

What is claimed is:

1. An integrated circuit comprising:
A. a bi-directional test clock lead for carrying a TCK in signal, a frame data in signal, and a frame data out signal;
B. a test mode select lead;
C. data circuitry having a frame data input and output connected to the test clock lead and having control inputs; and
D. state machine circuitry having inputs coupled to the test clock lead and to the test mode select lead, the state machine circuitry having control outputs…

Assignees

• Texas Instruments Inc

Inventors

• Whetsel Lee D

Classifications

• G01R31/3177

  Physics · mapped topic

• G06F11/267

  Physics · mapped topic

• G01R31/317 Primary

  Physics · mapped topic

• G01R31/318536

  Physics · mapped topic

• G01R31/318591

  Physics · mapped topic