By Adam Taylor

So far on our journey, every Zynq SoC and Zynq UltraScale+ MPSoC we have looked at has had two or more ARM microprocessor cores. However, I recently received the new Avnet MinZed dev board based on a Zynq Z-7007S SoC. This board is really exciting for several reasons. It is the first board we’ve looked at that’s based on a single-core Zynq SoC. (It has one ARM Cortex-A9 processor core that runs as fast as 667MHz in the speed grade used on the board.) And like the snickerdoodle, it comes with support for WIFI and Bluetooth. This is a really interesting board and it sells for a mere $89 in the US.

Xilinx designed the single-core Zynq for cost-optimized and low-power applications. In fact, we have been using just a single core for most of the Zynq-based applications we have looked at over this series unless we have been running Linux, exploring AMP, or looking at OpenAMP. One processor core is still sufficient for many, many applications.

The MiniZed dev board itself comes with 512Mbytes of DDR3L SDRAM, 128Mbits of QSPI flash memory, and 8Gbytes of eMMC flash memory. When it comes to connectivity, in addition to the wireless links, the MiniZed board also provides two PMOD interfaces and an Arduino/ChipKit Shield connector. It also provides an on-board temperature sensor, accelerometer and microphone.

Here’s a block diagram of the MiniZed dev board:





Thanks to its connectivity, its capabilities and low cost make the MiniZed board ideal for a range of applications, especially those applications that fall within the Internet of Things and Industrial Internet of Things domains.

When we first open the box, the MiniZed board comes preinstalled with a PetaLinux image loaded into the QSPI flash memory. This has a slight limitation as the QSPI flash is not large enough to host a PetaLinux image with both a Bluetooth and WIFI stack. Only the WIFI stack is present in the out-of-the-box condition. If we want to use the Bluetooth—and we do—we need to connect over WIFI and upload a new boot loader so that we can load a full-featured PetaLinux image from the eMMC flash. The first challenge of course is to connect over WIFI. We will look at that in the rest of this blog.

The first step is to download the demo application files from the MiniZed Website. This provides us with the following files which we need to use in the demo:

bin – a boot loader used to load the boot image from eMMC Flash

ub – PetaLinux with the Bluetooth stack

conf – Configuration file where we can define the WIFI SSID and Key

To correctly set up the MiniZed for our future adventures, we will also need a USB memory stick. On our host PC, we need to open the file wpa_supplicant.conf using a program like notepad++. We then add our network’s SSID and PSK so that the MiniZed can connect to our network. Once this is done, we save the file to the USB memory stick’s root.

Setting the WIFI SSID and PSK

The next step is to power on the MiniZed board and connect to a PC using a USB cable from the computer’s USB port to the MiniZed board’s JTAG UART connector. Connect a second USB cable from the MiniZed’s auxiliary input connector for power. We need to do this because of the USB port’s current supply limits. Without the auxiliary USB cable, we can’t be sure that the memory stick can be powered correctly when plugged into the MiniZed board.

Press the MiniZed board’s reset button and you should see the Linux OS boot in your terminal screen. Once booted, log in with the password and username of root.

We can then plug in the USB memory stick. The MiniZed board should discover the USB memory stick and you should see it reported in the terminal window:

Memory Stick detection

To log on to our WIFI network, we need to copy this file to the eMMC. To do this, we issue the following commands via the terminal.

These commands change the directory to the eMMC and erases anything within it before changing directory to the USB memory stick and listing the contents, where we should see our wpa_supplicant.conf file.

The next step is to copy the file from the USB memory stick to the eMMC and check that it has been copied correctly:

We are then ready to start the WIFI we can do this by navigating to

You should see this:

Now we are connected to the WIFI we can enable the blue tooth and transfer files wirelessly which we will look at next time.

Code is available on Github as always.

If you want E book or hardback versions of previous MicroZed chronicle blogs, you can get them below.

First Year E Book here

First Year Hardback here