abnormal signal in GPIO2 in 410-251-B board

[Aureliano]

Hi all,

 

This is the first time that I post here. I hope that I'm doing well.

We have a new design where we use a 410-251-B board in order to interface with JTAG a Zynq 7000 SoC. I used the following configuration suggested by Digilent:

With an oscilloscope I see the GPIO2 output (yellow) and I detect an amazing waveform. If the equipment is powered I see a stable signal, but if I select "Autoconnect" in Vivado I have the next signal:

 

Blue signal is the input of PS_SRST_B.

 

When a try download a bitfile, I have detected that GPIO2 waveform varies and sometimes this process is aborted (when PS_SRST_B have a low level). I show you two cases of this:

1.

2.

 

Do you have any idea about what is happening?

 

Thanks in advance.

 

Regards.

 

Manuel.