Datasheet

Boundary
32-bit Counter
SGPIO
Mode
0-3
Control
ID
ByPass
LFSR
MultiCast
PortEnable
Instruction
Selection
Control
TAP
Controller
Local
Scan
Port
Network
LSP
Controller
TCK
B0
TMS
B0
TRST
B0
S
0-7
TDI
B0
A0
B0
, A1
B0
Y0
B0
, Y1
B0
TDO
B0
Mode
0-3
TDI/TDO
Crossover
Master/
Slave
Logic
TDI
B1
, A0
B1
A1
B1
TMS
B1
TCK
B1
TRST
B1
TDO
B1
TRIST
B1
Y0
B1
Y1
B1
TRIST
B0
TDO
01
TCK
01
TMS
01
TRST
01
Y0
01
Y1
01
TRIST
01
TDI
01
A0
01
A1
01
LSPSel
0-6
MPSel
B1/B0
TRANS
TDO
02-03
TCK
02_03
TMS
02-03
TRST
02-03
TRIST
02-03
TDI
02-03
TDO
04-06
TCK
04-06
TMS
04-06
TRST
04-06
TDI
04-06
OE
MstrPortSel
ADDMASK
SB/S
RESET
TLR_TRST
TLR_TRST
6
TDI/TDO
Crossover
Master/
Slave
Logic
/
2
SCANSTA112
www.ti.com SNLS161I –DECEMBER 2002–REVISED APRIL 2013
The 'STA112 selection controller provides the functionality that allows the 1149.1 protocol to be used in a multi-
drop environment. It primarily compares the address input to the slot identification and enables the 'STA112 for
subsequent scan operations.
The Local Scan Port Network (LSPN) contains multiplexing logic used to select different port configurations. The
LSPN control block contains the Local Scan Port Controllers (LSPC) for each Local Scan Port (LSP
0
, LSP
1
...
LSP
n
). This control block receives input from the 'STA112 instruction register, mode registers, and the TAP
controller. Each local port contains all four boundary scan signals needed to interface with the local TAPs plus
the optional Test Reset signal (TRST).
The TDI/TDO Crossover Master/Slave logic is used to define the bidirectional B0 and B1 ports in a Master/Slave
configuration.
Block Diagram
Figure 3. SCANSTA112 Block Diagram
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Product Folder Links: SCANSTA112