SCANSTA111 National Semiconductor Corporation, SCANSTA111 Datasheet - Page 11

• Manufacturer Part Number: SCANSTA111
• Description: Enhanced Scan Bridge Multidrop Addressable Ieee 1149.1 Jtag Port
• Manufacturer: National Semiconductor Corporation

Level 1 Protocol (Addressing Modes)
Level 2 Protocol
Once the SCANSTA111 has been successfully addressed
and selected, its internal registers may be accessed via
Level-2 Protocol. Level-2 Protocol is compliant to IEEE Std.
1149.1 TAP protocol with one exception: if the ’STA111 is
selected via the Broadcast or Multi-Cast address, TDO
always TRI-STATED. (The TDO
FIGURE 7. Broadcast Addressing: Address Loaded into Instruction Register
FIGURE 8. Multi-Cast Addressing: Address Loaded into Instruction Register
B
buffer must be imple-
B
is
11
(Continued)
mented this way to prevent bus contention.) Upon being
selected, (i.e., the ’STA111 Selection controller transitions
from the Wait-For-Address state to one of the Selected
states), each of the local scan ports (LSP
remains parked in one of the following four TAP Controller
states: Test-Logic-Reset, Run-Test/Idle, Pause-DR, or
0
, LSP
www.national.com
1
, LSP
10124510
10124511
2
)