Libraries GuideChapter 10: Design Elements (SOP3 to XORCY_L)
TDO
Boundary Scan Data Output Pad
XC3000
| XC4000E
| XC4000X
| XC5200
| XC9000
| Spartan
| SpartanXL
| Spartan2
| Virtex
|
|---|
N/A
| Primitive
| Primitive
| Primitive
| N/A
| Primitive
| Primitive
| N/A
| N/A
|
The TDO data output pad is connected to the boundary scan TDO output. It is connected to the external circuit to provide the boundary scan data for each Low-to-High TCK transition. The function of the TDO pad is device configuration dependent and can be used as follows.
- During configuration, TDO is connected to the boundary scan logic.
- After configuration, if boundary scan is not used, the TDO pad can be used as a 3-state output pad by the routing tool.
- After configuration, if boundary scan is used, the TDO pad is still used as an output from the boundary scan logic.
