Pynq 2.7 for Zybo-Z7

Hi everyone, I hope you’re okay. I was following this post by PeterOgden to create a Pynq 2.7 image for Zybo-Z7 and thought in sharing my experience.

For those interested in recreating the image you can follow these stages.

1. Create the Board Support Package (BSP) (30 min approx.)
Although the Pynq-Z2 and the Zybo-Z7 have the same FPGA (i.e. xc7Z020-clg400), they present some differences. So, the following specifications should be considered for the Zybo-Z7.

  • DDR part number: MT41K256M16 RE-125.
  • The PS UART1 is routed to the FTDI instead of the UART0 for the Pynq-Z2.
  • The Crystal oscillator has a frequency of 33.3333 MHz.

The Zybo-Z7/petalinux_bsp/hardware_project/zyboz7.tcl file was modified to considered the aforementioned. Also, the block diagram for the bsp is shown in bd_layout.pdf (38.4 KB).

  • $ source /tools/Xilinx/Vitis/2020.2/
  • $ source ~/petalinux/2020.2/
  • $ petalinux-util --webtalk off
  • Make sure that ~/PYNQ/boards/Zybo-Z7/Zybo-Z7.spec has the line BSP_Zybo-Z7 :=
  • $ cd ~/PYNQ/sdbuild
  • $ make bsp BOARDDIR=/home/user/PYNQ/boards BOARDS=“Zybo-Z7”
  • copy the bsp file from ~/PYNQ/sdbuild/output/bsp/Zybo-Z7/xilinx-zyboz7-2020.2.bsp to ~/PYNQ/boards/Zybo-Z7/. Thus, along the Zybo-Z7.spec.
  • Add the bsp to the Zybo-Z7.spec: BSP_Zybo := xilinx-zyboz7-2020.2.bsp.

2. Create the image (2h30 min approx.)
To make the port process simple, I deleted the logictools overlay and reduce the base overlay deleting the Arduino and Raspberry Pi peripherals. Also, I modified the Makefile inside the sdbuild folder to avoid compiling for all the boards (Pynq-Z1, Pynq-Z2, ZCU-104, sw_repo). The changes are after the Pynq repository is cloned in line 65 (you can check this changes in the file Makefile_sdbuild shared).
This changes also affect the ~/PYNQ/ file.
The base overlay block diagram is shown in bd_layout.pdf (107.0 KB). Also the constraints file base.xdc was updated from the Zybo-Z7 master xdc.
The steps used were:

  • Download the PYNQ rootfs arm v2. 7 found in PYNQ - Python productivity for Zynq - Board The downloaded file is named focal.arm.2.7.0_2021_11_17.tar.gz and will be placed in ~/PYNQ/sdbuild/.
  • $ cd ~/PYNQ/sdbuild
  • $ make BOARDDIR=/home/user/PYNQ/boards BOARDS=“Zybo-Z7” PREBUILT=focal.arm.2.7.0_2021_11_17.tar.gz nocheck_images
  • Wait patiently, be happy :yum:

The image file named Zybo-Z7-2.7.0.img will be stored in ~/PYNQ/sdbuild/output. Its size will be around 7.6 GB.

3. Copy image to micro SD card (20 min approx.)
The steps used were:

  • $ cd ~/PYNQ/sdbuild/output
  • $ df -h
  • Select the device corresponding to your SD card. Be careful, you could damage your OS if choose wrong.
  • $ umount /dev/sXX1 (for instance mine was in /dev/sdb1).
  • $ sudo dd bs=4M if=Zybo-Z7-2.7.0.img of=/dev/sXX status=progress

That’s it :smiley:.
I know these instructions can be vague and lack of deep explanations. But my intention is to share the stages I followed, so you can adjust them to your own needs.


First thank you for showing such great example to this community.
Meantime, I would like to know if there is any issue or setting require on run the Makefile you modified?
It looks like extracting:
sed -e '105,165d' $(BUILD_ROOT)/PYNQ/
Still running the entire sh script and ends up building all.
Thank you

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Hi Brian, I hope you’re doing great :-). Issues could be present as each time you run the Makefile, git makes changes locally. To make sure the file is getting modified, you should check the ~/PYNQ/sdbuild/build/ directory and search for the copied there. Lines after the 105 are not needed (since they are forcing the Pynq repo to be cloned again for the Pynq-Z2 and compile the original overlays). One workaround could be to just delete those lines by hand.
I’m sorry I can’t guarantee the Makefile given will work as it is, because among tests I loss track of the changes made to my local copy of the PYNQ repository :sweat_smile:.
However, I’m sure you could get it working following the aforementioned :smiley: Please, let me know as soon as you get it.


Hello Dorfell and Thank you for sharing your work here. I almost managed to rebuilt the Image completely Thanks to you! Actually I rebuilt it… but I have a problem with the ethernet: No IP adress at boot on eth0.

when I make an ifconfig:

root@pynq:~$ ifconfig
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::218:3eff:fe03:dc9e prefixlen 64 scopeid 0x20
ether 00:18:3e:03:dc:9e txqueuelen 1000 (Ethernet)
RX packets 86 bytes 17859 (17.8 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 394 bytes 110809 (110.8 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
device interrupt 28 base 0xb000

eth0:1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet netmask broadcast
ether 00:18:3e:03:dc:9e txqueuelen 1000 (Ethernet)
device interrupt 28 base 0xb000

lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet netmask
inet6 ::1 prefixlen 128 scopeid 0x10
loop txqueuelen 1000 (Local Loopback)
RX packets 2320 bytes 175853 (175.8 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 2320 bytes 175853 (175.8 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

I tried this:
$ ifup eth0
Internet Systems Consortium DHCP Client 4.4.1
Copyright 2004-2018 Internet Systems Consortium.
All rights reserved.
For info, please visit ISC DHCP - ISC

Listening on LPF/eth0/00:18:3e:03:dc:9e
Sending on LPF/eth0/00:18:3e:03:dc:9e
Sending on Socket/fallback
DHCPDISCOVER on eth0 to port 67 interval 3 (xid=0xa68db745)
DHCPDISCOVER on eth0 to port 67 interval 4 (xid=0xa68db745)
DHCPDISCOVER on eth0 to port 67 interval 4 (xid=0xa68db745)
No DHCPOFFERS received.
No working leases in persistent database - sleeping.

At least it explains why I can’t connect through ethernet but I have no idea how to solve this
So here is my question : did you made any changes in the device tree or something to have a proper eth0 interface?

I am using a Zybo-Z7-20

Hi Lenny, ¡that’s sounds great :grin:!!!. To answer your question, I didn’t modify any device tree files. Actually the file located in petalinux_bsp/meta-user/recipes-bsp/device-tree/files/system-user.dtsi is the same from the Pynq-Z2 example. However, it is important to make sure the Ethernet package is added in the ZyboZ7.spec file. For instance, I have this line STAGE4_PACKAGES_Zybo-Z7 := xrt pynq boot_leds ethernet pynq_peripherals. On the other hand, I used the Ethernet ports from the router of my internet service provider, which I have previously tested with a Linux laptop to verify it was working okay.
I hope you can find out a solution. The image shared in the post is also for the Zybo-Z7-20, maybe you can check if that image works on your board to discard external problems ?
Regards :smiley:

Hi Lenny, I forgot to ask you if you had checked the IP showed in your message (i.e. inet
This because the IP is dynamically assigned according to your router demand. In addition, as far I remember, I didn’t configure the static IP for this Pynq image, although according to the documentation, this is possible.
Have a nice day :slight_smile:

Thanks for your sharing.
I’m interesting about the step you mention:

$ make bsp BOARDDIR=/home/user/PYNQ/boards BOARDS=“Zybo-Z7”
copy the bsp file from ~/PYNQ/sdbuild/output/bsp/Zybo-Z7/xilinx-zyboz7-2020.2.bsp to ~/PYNQ/boards/Zybo-Z7/. Thus, along the Zybo-Z7.spec.
Add the bsp to the Zybo-Z7.spec: BSP_Zybo := xilinx-zyboz7-2020.2.bsp.

Does this step should be skipped.
I check the RreadMe, if keep the BSP_Zybo can be empty because make will search the petalinux_bsp folder and trying to build the xsa and BSP directly.

1 Like

Hi @Willy thanks for pointing it out :smiley:, I missed it :sweat_smile:.

Hello Dorfell, thank you sooo much for sharing your work here. I am using a Zybo-Z7-20 and I would like to run tensorflow code on Zybo so I think I can use the image which you put on the google drive directly.

What I did:

  1. copy the image to SD card and insert it into zybo
  2. connect Zybo to my computer via micro USB cable

My problem:
No “ttyusb0” show up in the /dev, I tap “sudo dmesg | grep tty” and nothing’s new no matter i turn on or off the Zybo via the switch. So I can’t establish communication using UART.

Do you have any idea how to fix it or whether I missed some steps?
Thank you

Hi Yongtao, I’m sorry for my late reply. After reading about your problem, some naive questions arise:

  • Is board JP5 in the SD card position?
  • Is LD12 (a.k.a Done) turn on after several seconds?
  • What’s your output for ls /dev?. The Zybo could appear as ttyUSB0, ttyUSB1, ttyUSB2, etc.

Besides, I’m using cutecom because it lists the uart devices available. A part from dmesg what are you using?
Let me know if you have any update,
Best wishes,
Dorfell :slight_smile:

Hello Dorfell!
Thank you for responding me I kinda forgot to answer you however! I managed to make ethernet work properly. It was not a device-tree issue but a problem of setup on my side ^^'. Connect to a DHCP server, it will work better!

If some people have troubles building it here are the additional fixes I made to dorfell’s project:
I changed the deleting all lines after line 102.
In the Makefile I added some lines in order to delete completely all default boards folders and copy my customized, after git checkout (line 68):

	cd $(BUILD_ROOT)/PYNQ && git fetch origin && git checkout $(PYNQ_MASTER_COMMIT)
	rm -rf $(BUILD_ROOT)/PYNQ/boards/Pynq-Z1
	rm -rf $(BUILD_ROOT)/PYNQ/boards/Pynq-Z2
	rm -rf $(BUILD_ROOT)/PYNQ/boards/ZCU104
	rm -rf $(BUILD_ROOT)/PYNQ/boards/sw_repo
	rm -rf $(BUILD_ROOT)/PYNQ/

I have to warn you that the image you uploaded did not work for me (corrupted or something because failed to flash the SDCard), it is the reason why I tried to build it myself!

Thank you again for sharing your work, it really helped me out a LOT!!

Have a nice day! :smile:


¡Great Lenny!!!. Thanks a lot for your feedback :slight_smile:
Have a great day too :smiley: