DS3154+ Maxim Integrated Products, DS3154+ Datasheet - Page 33

• Manufacturer Part Number: DS3154+
• Description: IC LIU DS3/E3/STS1 QUAD 144CSBGA
• Manufacturer: Maxim Integrated Products
• Type: Line Interface Units (LIUs)r

Specifications of DS3154+

• Number Of Drivers/receivers: 4/4
• Protocol: IEEE 1149.1
• Voltage - Supply: 3.135 V ~ 3.465 V
• Mounting Type: Surface Mount
• Package / Case: 144-CSBGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

12.2
This section discusses the operation of the TAP controller state machine. The TAP controller is a finite state
machine that responds to the logic level at JTMS on the rising edge of JTCLK. Each of the states denoted in
12-2
Figure 12-2. JTAG TAP Controller State Machine
Test-Logic-Reset. Upon device power-up, the TAP controller starts in the Test-Logic-Reset state. The instruction
register contains the IDCODE instruction. All system logic on the device operates normally.
Run-Test-Idle. Run-Test-Idle is used between scan operations or during specific tests. The instruction and test
registers remain idle.
Select-DR-Scan. All test registers retain their previous state. With JTMS low, a rising edge of JTCLK moves the
controller into the Capture-DR state and initiates a scan sequence. JTMS high moves the controller to the Select-
IR-SCAN state.
Capture-DR. Data can be parallel loaded into the test data registers selected by the current instruction. If the
instruction does not call for a parallel load or the selected register does not allow parallel loads, the test register
remains at its current value. On the rising edge of JTCLK, the controller goes to the Shift-DR state if JTMS is low or
to the Exit1-DR state if JTMS is high.
are described in the following pages.
JTAG TAP Controller State Machine Description
1
0
Test-Logic-Reset
Run-Test/Idle
0
1
DS3151/DS3152/DS3153/DS3154 Single/Dual/Triple/Quad DS3/E3/STS-1 LIUs
1
0
Capture-DR
1
Select
DR-Scan
Shift-DR
Pause-DR
Update-DR
Exit1- DR
Exit2-DR
33 of 61
0
0
1
0
1
1
0
1
0
1
0
1
0
Capture-IR
1
Select
IR-Scan
Shift-IR
Exit1-IR
Pause-IR
Exit2-IR
Update-IR
0
0
1
0
1
1
0
1
0
1
0
Figure