IDT JTAG Boundary Scan
Signal Definitions
PES12N3 User Manual
11 - 2
June 7, 2006
Notes
The TAP controller transitions from state to state, according to the value present on JTAG_TMS, as
sampled on the rising edge of JTAG_TCK. The Test-Logic Reset state can be reached either by asserting
JTAG_TRST_N or by applying a 1 to JTAG_TMS for five consecutive cycles of JTAG_TCK. A state diagram
for the TAP controller appears in Figure 11.2. The value next to state represent the value that must be
applied to JTAG_TMS on the next rising edge of JTAG_TCK, to transition in the direction of the associated
arrow.
Figure 11.2 State Diagram of PES12N3’s TAP Controller
Pin Name Type
Description
JTAG_TRST_N
Input
JTAG RESET
Asynchronous reset for JTAG TAP controller (internal pull-up)
JTAG_TCK
Input
JTAG Clock
Test logic clock. JTAG_TMS and JTAG_TDI are sampled on the rising edge.
JTAG_TDO is output on the falling edge.
JTAG_TMS
Input
JTAG Mode Select. Requires an external pull-up.
Controls the state transitions for the TAP controller state machine (internal pull-up)
JTAG_TDI
Input
JTAG Input
Serial data input for BSC chain, Instruction Register, IDCODE register, and BYPASS
register (internal pull-up)
JTAG_TDO
Output JTAG Output
Serial data out. Tri-stated except when shifting while in Shift-DR and SHIFT-IR TAP con-
troller states.
Table 11.1 JTAG Pin Descriptions
Test- Logic
Reset
Run-Test/
Idle
Select-
DR-Scan
Capture-DR
Shift-DR
Exit1 -DR
Pause-DR
Exit2-DR
Select-
IR-Scan
Capture-IR
Shift-IR
Exit1-IR
Pause-IR
Exit2-IR
Update-DR
Update-IR
1
1
0
0
0
1
1
0
0
1
1
0
1
0
1
0
0
1
1
1
0
0
1
1
0
1
0
1
1
0
0
0
0
Summary of Contents for 89HPES12N3
Page 10: ...IDT Table of Contents PES12N3 User Manual iv June 7 2006 Notes...
Page 14: ...IDT List of Figures PES12N3 User Manual viii June 7 2006 Notes...
Page 36: ...IDT Clocking Reset and Initialization Reset PES12N3 User Manual 2 8 June 7 2006 Notes...
Page 40: ...IDT Link Operation Slot Power Limit Support PES12N3 User Manual 3 4 June 7 2006 Notes...
Page 50: ...IDT Switch Operation Switch Core Errors PES12N3 User Manual 4 10 June 7 2006 Notes...
Page 54: ...IDT Power Management Active State Power Management PES12N3 User Manual 5 4 June 7 2006 Notes...
Page 62: ...IDT Hot Plug and Hot Swap Hot Swap PES12N3 User Manual 6 8 June 7 2006 Notes...
Page 78: ...IDT SMBus Interfaces Slave SMBus Interface PES12N3 User Manual 7 16 June 7 2006 Notes...
Page 148: ...IDT Test and Debug SerDes Test Clock PES12N3 User Manual 10 6 June 7 2006...
Page 158: ...IDT JTAG Boundary Scan Usage Considerations PES12N3 User Manual 11 10 June 7 2006 Notes...
