SCANSTAEVK/NOPB National Semiconductor, SCANSTAEVK/NOPB Datasheet - Page 2

• Manufacturer Part Number: SCANSTAEVK/NOPB
• Manufacturer: National Semiconductor

Specifications of SCANSTAEVK/NOPB

• Lead Free Status / RoHS Status: Compliant

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LFSR
LSP
Local
Park/Unpark/Unparked Parked, unpark, and unparked, are used to describe the state of the LSP controller and the state of the
TAP
Selected/Unselected
Active Scan Chain
Level 1 Protocol
Level 2 Protocol
PAD
LSB
MSB
Linear Feedback Shift Register. When enabled, will generate a 16-bit signature of sampled serial test
data.
Local Scan Port. A four signal port that drives a local (i.e. non-backplane) scan chain. (e.g., TCK
TDO
Local is used to describe IEEE Std. 1149.1 compliant scan rings and the SCANSTA111 Test Access Port
that drives them. The term local was adopted from the system test architecture that the ’STA111 will most
commonly be used in; namely, a system test backplane with a ’STA111 on each card driving up to 3 local
scan rings per card. (Each card can contain multiple ’STA111s, with 3 local scan ports per ’STA111.)
local TAP controllers (the local TAP controllers refers to the TAP controllers of the scan components that
make up a local scan ring). Park is also used to describe the action of parking a LSP (transitioning into
one of the Parked LSP controller states). It is important to understand that when a LSP controller is in
one of the parked states, TMS
given state.
Test Access Port as defined by IEEE Std. 1149.1.
Selected and Unselected refers to the state of the ’STA111 Selection Controller. A selected ’STA111 has
been properly addressed and is ready to receive Level 2 protocol. Unselected ’STA111s monitor the
system test backplane, but do not accept Level 2 protocol (except for the GOTOWAIT instruction). The
data registers and LSPs of unselected ’STA111s are not accessible from the system test master.
The Active Scan Chain refers to the scan chain configuration as seen by the test master at a given
moment. When a ’STA111 is selected with all of its LSPs parked, the active scan chain is the current
scan register only. When a LSP is unparked, the active scan chain becomes: TDI
register → the local scan ring registers → a PAD bit → TDO
configurations of the LSP network.
Level 1 is the protocol used to address a ’STA111.
Level 2 is the protocol that is used once a ’STA111 is selected. Level 2 protocol is IEEE Std. 1149.1
compliant when an individual ’STA111 is selected.
A one bit register that is placed at the end of each local scan port scan-chain. The PAD bit eliminates the
prop delay that would be added by the ’STA111 LSPN logic between TDI
buffering and synchronizing the LSP TDI inputs to the falling edge of TCK
scanned at higher frequencies without violating set-up and hold times.
Least Significant Bit, the right-most position in a register (bit 0).
Most Significant Bit, the left-most position in a register.
0
, TDI
0
).
n
TABLE 1. Glossary
is held constant, thereby holding or parking the local TAP controllers in a
2
B
. Refer to Table 7 for Unparked
n
B
and TDO
, thus allowing data to be
B
→ the current ’STA111
(n+1)
or TDO
B
0
, TMS
by
0
,