Answers Database
JTAG - How to attach a pullup or pulldown resistor on the 4K TDO pin?
Record #1358
Product Family: Software
Product Line: FPGA Implementation
Product Part: bitgen
Product Version: 1.5i
Problem Title:
JTAG - How to attach a pullup or pulldown resistor on the 4K TDO pin?
Problem Description:
General Description:
How to access the pullup or pulldown in the TDO IOB in a XC4000
series device if the TDO pin is being used as an output or OBUFT?
Solution 1:
It is possible to attach the pullup or pulldown to the TDO pin
using MAKEBITS in the XACT 5.x, 6.x software.
Run makebits with the following option:
makebits -f TdoPin: Pullup | Pulldown <lca file>
Note: It is not possible to access this feature via XDE. You can
only see the TDO component, however not edit it.
Solution 2:
It is possible to attach the pullup or pulldown to the TDO pin
using BITGEN in the M1 software.
Run bitgen with the following option:
bitgen -g TdoPin:Pullnone | Pullup | Pulldown <infile[.ncd]>
[<outfile>] [<pcffile[.pcf]>]
Note: It is not possible to access this feature via EPIC. You can
only see the TDO component, however not edit it.
End of Record #1358 - Last Modified: 01/10/00 22:10 |
