AR# 1358

*Obsolete* JTAG - How to attach a pullup or pulldown resistor on the 4K TDO pin?

描述

Keywords: xc4000, xc4000e, xc4000x, xc4000xl, xde, epic, pullup, pulldown, tdo, makebits, BitGen

Uregency: Standard

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?


解决方案

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 you cannot edit it.

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 you cannot edit it.
AR# 1358
日期 09/22/2005
状态 Archive
Type ??????