I have a chain with an XILINX-XC9572XL-CPLD. I could not program or access the CPLD when STPC Elite is in the chain. If I cut STPC Elite out of the chain the access to CPLD is without any problems. Could the SCAN_ENABLE the problem? I have tied it to GND. Benno
The Scan_Enable pin is a reserved pin on the STPC. It is used for manufacturing testing purposes only and should not be set any other value than that given the schematics.
Also, the JTAG in the STPC Elite (and all the others for that matter) is only used for Boundary scan purposes only. It cannot be used for any thing else. If you want to programme external flashes or EPLDs for example, you must implement 2 scan chains.