SCANSTA112
SNLS161I –DECEMBER 2002–REVISED APRIL 2013
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PIN DESCRIPTIONS
No.
Pin Name Pins I/O Description
VCC 10 N/A Power
GND 10 N/A Ground
RESET 1 I RESET Input: will force a reset of the device regardless of the current state.
ADDMASK 1 I ADDRESS MASK input: Allows masking of lower slot input pins.
MPselB1/B0 1 I MASTER PORT SELECTION: Controls selection of LSPB0 or LSPB1 as the backplane port. The
unselected port becomes LSP00. A value of "0" will select LSPB0 as the master port.
SB/S 1 I Selects ScanBridge or Stitcher Mode.
LSPsel (0-6) 7 I In Stitcher Mode these inputs define which LSP's are to be included in the scan chain
TRANS 1 I Transparent Mode enable input: The value of this pin is loaded into the TRANSENABLE bit of the
control register at power-up. This value is used to control the presence of registers and pad-bits in
the scan chain while in the stitcher mode.
TLR_TRST 1 I Sets the driven value of TRST0-5 when LSP TAPs are in TLR and the device is not being reset.
During RESET = "0" or TRSTB= "0" (IgnoreReset = "0") TRSTn= "0". This pin is to be tied low to
match the function of the SCANSTA111
TLR_TRST61 I This pin affects TRST of LSP6only. This pin is to be tied low to match the function of the
SCANSTA111
TDIB0, TDIB1 2 I BACKPLANE TEST DATA INPUT: All backplane scan data is supplied to the 'STA112 through this
input pin. MPselB1/B0 determines which port is the master backplane port and which is LSP00. This
input has a 25KΩinternal pull-up resistor and no ESD clamp diode (ESD is controlled with an
alternate method). When the device is power-off (VDD floating), this input appears to be a capacitive
load to ground (1). When VDD = 0V (i.e.; not floating but tied to VSS) this input appears to be a
capacitive load with the pull-up to ground.
TMSB0, TMSB1 2 I/O BACKPLANE TEST MODE SELECT: Controls sequencing through the TAP Controller of the
'STA112. Also controls sequencing of the TAPs which are on the local scan chains. MPselB1/B0
determines which port is the master backplane port and which is LSP00. This bidirectional TRI-
STATE pin has 24mA of drive current, with a 25KΩinternal pull-up resistor and no ESD clamp
diode (ESD is controlled with an alternate method). When the device is power-off (VDD floating), this
input appears to be a capacitive load to ground (1). When VDD = 0V (i.e.; not floating but tied to VSS)
this input appears to be a capacitive load with the pull-up to ground.
TDOB0, TDOB1 2 I/O BACKPLANE TEST DATA OUTPUT: This output drives test data from the 'STA112 and the local
TAPs, back toward the scan master controller. This bidirectional TRI-STATE pin has 12mA of drive
current. MPselB1/B0 determines which port is the master backplane port and which is LSP00. Output
is sampled during interrogation addressing. When the device is power-off (VDD = 0V or floating), this
output appears to be a capacitive load (1).
TCKB0, TCKB1 2 I/O TEST CLOCK INPUT FROM THE BACKPLANE: This is the master clock signal that controls all
scan operations of the 'STA112 and of the local scan ports. MPselB1/B0 determines which port is the
master backplane port and which is LSP00. These bidirectional TRI-STATE pins have 24mA of drive
current with hysterisis. This input has no pull-up resistor and no ESD clamp diode (ESD is controlled
with an alternate method). When the device is power-off (VDD floating), this input appears to be a
capacitive load to ground (1). When VDD = 0V (i.e.; not floating but tied to VSS) this input appears to
be a capacitive load to ground.
TRSTB0, TRSTB1 2 I/O TEST RESET: An asynchronous reset signal (active low) which initializes the 'STA112 logic.
MPselB1/B0 determines which port is the master backplane port and which is LSP00. This
bidirectional TRI-STATE pin has 24mA of drive current, with a 25KΩinternal pull-up resistor and no
ESD clamp diode (ESD is controlled with an alternate method). When the device is power-off (VDD
floating), this pin appears to be a capacitive load to ground (1). When VDD = 0V (i.e.; not floating but
tied to VSS) this input appears to be a capacitive load with the pull-up to ground.
TRISTB0, TRISTB1,5 O TRI-STATE NOTIFICATION OUTPUT: This signal is asserted high when the associated TDO is
TRIST(01-03) TRI-STATEd. Associated means TRISTB0 is for TDOB0, TRIST01 is for TDO01, etc. This output has
12mA of drive current.
A0B0, A1B0, A0B1,4 I BACKPLANE PASS-THROUGH INPUT: A general purpose input which is driven to the Ynof a
A1B1 single selected LSP. (Not available when multiple LSPs are selected). This input has a 25KΩ
internal pull-up resistor. MPselB1/B0 determines which port is the master backplane port and which is
LSP00.
Y0B0, Y1B0, Y0B1,4 O BACKPLANE PASS-THROUGH OUTPUT: A general purpose output which is driven from the Anof
Y1B1 a single selected LSP. (Not available when multiple LSPs are selected). This TRI-STATE output has
12mA of drive current. MPselB1/B0 determines which port is the master backplane port and which is
LSP00.
(1) Refer to the IBIS model on our website for I/O characteristics.
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