KV260 read mipi frame stuck on dma, help

Hi Mario,

I hope this reaches you,

I have continued with my endeavour, attempting get the MIPI camera (digilent PCAM5C) streaming through to the top level Jupyter notebooks environment on the PYNQ framework with my KV260.

After investigating Adam taylor’s design () I was able to use his vitis application to prove that my PCAM was working - getting a stream that i could display to the HDMI to a monitor. I then copied his driver format and translated into python, trying to run as cells - writing to the sequence of registers he detailed.
note: There were some minor differences between his driver and the pcam5c.py driver under the PYNQ layers. Mainly in how he repeated particular writes down the I2C for resets, commands to configure VDMA and Videomode (these are handled differently in PYNQ I assume with the other files and functions e.g. dma.py and VideoMode function) .

When trialing this driver, it worked up until the very last register I had to write to: 0x02 to register 0x3008. This is done in the PYNQ driver file as below:

So with this failing, and an uncertainty as to why I turned to comparing the hardware design, and looking to make minor tweaks to the PYNQ hardware design adding in ILAs as you suggested. To ensure the Axi Stream data passed from one block to the next - not getting held up awaiting an axi Stream TReady signal from the next block, I added in a FIFO as the next block in the chain - planning to test the movement of the Axi Stream through each block from MIPI RX subsytem to VDMA. Such as below:

I then run synth,impl and gen the bitstream before turning to the hardware manager. Here I a connect the board via JTAG and power up the board with all peripherals already connected. The K26 Som is detected but no ILAs show in the Hardware tab underneath.

As the board boots up, it enters as bootup sequence I dont recognise, and vivado tcl console prompts the critical warning:

*[Labtools 27-3421] xck26_0 PL Power Status OFF cannot connect PL TAP. Check Por_B signal*

After a while the board then enters the regular bootup sequence. But along the way I have noticed that it says the Jupyter notebooks server fails to launch. This is then reinforced once I am logged into the ubuntu user:

I have been reading up and found this discussion: Problem with Using integrated logic analyzer (ILA) for Debugging with PYNQ - #5 by parsonsk That suggests you cant use the JTAG to debug and the Jupyter notebooks at the same time out of the box

Is this the correct next port of call, do I have to add this to the SD card and re flash the board with this code or is there a change to this code for the KV260? I can’t find any other examples of people using boards with PYNQ to debug using the hardware manager to view ILA data.

Thought I’d update the thread with what I have attempted and found. Am I going down the right avenues, do you have any further suggestions?


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