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5 shift-dr state, 6 exit1-dr state, 7 pause-dr state – Intel CONTROLLERS 413808 User Manual

Page 787: 8 exit2-dr state, 9 update-dr state

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Intel

®

413808 and 413812 I/O Controllers in TPER Mode

October 2007

Developer’s Manual

Order Number: 317805-001US

787

Test Logic Unit and Testability—Intel

®

413808 and 413812

18.2.2.5 Shift-DR State

In this controller state, the test data register, which is connected between

TDI

and

TDO

as a result of the current instruction, shifts data one bit position nearer to its

serial output on each rising edge of

TCK

. Test data registers that the current instruction

select but do not place in the serial path, retain their previous value during this state.
The instruction does not change while the TAP controller is in this state.
Transition to next state: When

TMS

is high on the rising edge of

TCK

, move to

Exit1-DR, else remain at Shift-DR.

18.2.2.6 Exit1-DR State

This is a temporary controller state.
All test data registers selected by the current instruction retain their previous value

during this state. The instruction does not change while the TAP controller is in this

state.
Transition to next state: When

TMS

is held high on the rising edge of

TCK

, the

controller enters the

Update-DR

state and the scanning process terminates. When

TMS

is held low on the rising edge of

TCK

, the controller enters the

Pause-DR

state.

18.2.2.7 Pause-DR State

The

Pause-DR

state allows the test controller to temporarily halt the shifting of data

through the test data register in the serial path between

TDI

and

TDO

.

All test data registers selected by the current instruction retain their previous value

during this state. The instruction does not change while the TAP controller is in this

state.
Transition to next state: When

TMS

is high on the rising edge of

TCK

, move to the

Exit2-DR, else remain at Pause-DR.

18.2.2.8 Exit2-DR State

This is a temporary state.
All test data registers selected by the current instruction retain their previous value

during this state. The instruction does not change while the TAP controller is in this

state.
Transition to next state: When

TMS

is high on the rising edge of

TCK

, the controller

enters the Update-DR state and the scanning process terminates. When TMS is held

low on the rising edge of

TCK

, the controller re-enters the Shift-DR state

18.2.2.9 Update-DR State

Data is latched into the parallel output of shift registers from the shift register path, on

the falling edge of

TCK

.

All of the test data register’s shift-register bit positions selected by the current

instruction retain their previous values. The instruction does not change while the TAP

controller is in this state.
Transition to next state: When

TMS

remains high on the rising edge of

TCK

, then the

controller moves to the Select-DR state, else the controller moves to the Run-Test/Idle

state.