Downloading configuration to CPLD ICs using PC and LPT parallel cables

date modified 21-11-2020


Schematics of Xilinx download LPT cable:
PDF "XTP029 (v1.0) March 28, 2008 Overview of Xilinx JTAG Programming Cables and Reference Schematics for Legacy Parallel Cable III (PC3)"
PDF 1 page schematic (Date: July 10, 1996)
PDF "JTAG Programmer Guide" 1 meg file
X7556 schematic gif-image
File from ""
A jtag page at The 6-pin header is nearly has nearly the same order of signals on it as with what I've used in my library in the Eagle pcb cad software, except the pin numbering is reversed (1-6/6-1.)
Indeed the pin arrangement in a jtag connector is not strictly standardised, but quite many variations are used. Also test pads for jtag signals could be spread around the pcb, instead of an in-line connector.
("Google" should find more documents.)

The direct download links have not worked for a long time. To download, you need to register first at The last ISE version, V14.7 needs certain file renaming to work on windows 10. For ABEL support you need older releases. Webpack ISE 4.2WP3.0 installs directly, it doesn't have that newer verilog 2001 support for "always @*". ISE version 6 : the needed registration id-string can be simply downloaded.
NOTE: most LINKS OLD NOT WORKING XC9500 lpt download cable software (I used this one on a W95 laptop) An "older" version (4.2) of Xilinx Webpack software (Later version are bigger downloads.) source for above direct download links.


See dcn-2692 project's page.