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Observer cdv16
Registered: ‎06-07-2019

JTAG Port not working

The JTAG interface on the Kintex-7 FPGA KC705 Evaluation Board has been behaving unpredictably and eventually stopped working. At first, when I flashed a bitstream + ELF, it worked about 80% of the time, the remaining 20% required moving the micro-USB slightly and re-flashing. But eventually it stopped recognizing the device altogether. I verified that there is good connectivity and no shorts with a multimeter and a microscope. What should be the next step? Is there a JTAG troubleshooting tool? Should I get a new Diligent JTAG module? Here is the error message:  errormessage.PNG


And the output of the SDK Log: 

09:33:02 INFO	: Launch script is exported to file 'C:\Users\Public\VivadoStuff\fmc_attempt_1\fmc_attempt_1.sdk\.sdk\launch_scripts\xilinx_c-c++_application_(system_debugger)\system_debugger_using_debug_helloworld.elf_on_local.tcl'
09:35:11 INFO	: Connected to target on host '' and port '3121'.
09:35:11 INFO	: 'targets -set -filter {jtag_cable_name =~ "Digilent JTAG-SMT1 210203A5FCDBA" && level==0} -index 0' command is executed.
09:35:23 ERROR	: (XSDB Server)-code 1 -level 0 -errorcode NONE -errorinfo {Code 1 Time 1560173723208 Format {FT_Read returned 0, expected 5}
    while executing
"error [lindex $data 0]"
    invoked from within
"if { [lindex $data 0] != "" } {
		    error [lindex $data 0]
    ("eval" body line 2)
    invoked from within
"eval $script"} -errorline 12

09:35:23 INFO	: FPGA configured successfully with bitstream "C:/Users/Public/VivadoStuff/fmc_attempt_1/fmc_attempt_1.sdk/system_wrapper_hw_platform_0/download.bit"



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Xilinx Employee
Xilinx Employee
Registered: ‎06-06-2018

Re: JTAG Port not working

Hi @cdv16 ,

Revison version of the board?

1. Please share the power good LEDS Snapshot of the board at power ON.

2. Are you facing this issue at time 0 or after period of usage?

3. Please go through this KC705 debug Checklist and confirm me till Step 4 you are fine?

4. Is the board getting detected through Vivado Hardware manager? Please share the Snapshot.

5. Also share the cable detection Snapshot in PC device manager when board is connected to PC via JTAG cable at power ON, JTAG Cable will get detected under universal serail bus controllers section.

6. Please share the Vivado version and OS Details.



Deepak D N


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