Raspberry Pi Zero 2W, a quad-core mini SBC for 15 €

Single Board Computers such as the new Raspberry Pi Zero 2W are an electronic basis for products and prototypes . You know, there is always a halo of hype when the Raspberry Pi foundation announces a new product. This time it is the new and awaited successor of the “Zero” series, characterized by dimensions and costs reduced to the bone, even for the narrow standards of SBCs. To justify this hype is the certainty, on the part of users, to see these cards used for the most disparate projects, with support from third-party developers and the community of makers that has no equal, the company's real strength.

The Raspberry Pi Zero 2W

The novelty is mainly to be found in the new SoC composed of the Broadcom BCM2710A1 processor, featuring four 64-bit ARM Cortex-A53 cores at 1GHz. Miniaturizing a SoC with performance on par with the Raspberry Pi 3 is not an easy task; it was possible by integrating the RAM in the same package as the SoC. This technique is called system-in-package (SiP). The foundation claims that the upgraded processor is 40% faster in single-threaded operations , and 5x faster in multi-threaded operations, than the first single-core Raspberry Pi Zero.

Raspberry Pi Zero 2W SoC. Source: RaspberryPi
Raspberry Pi Zero 2W SoC. Source: RaspberryPi

Independent tests have shown that the Raspberry Pi is also capable of abundantly exceeding the official promises in specific tests such as 7-Zip data compression, video Encoding and OCR (Optical Carachter Recognition), reaching benchmarks up to 10 times higher than the previous model. all while maintaining an energy consumption that is at times comparable. In fact in idle, or with the minimum of active processes, the consumption is less than 100 mAh.

The Pi Zero W is satisfied with around 75 mah, while the Pi3B + absorbs 350 mah. Different speech at full load with a stress-test such as stress-ng, during which it never exceeds 450mah (the Pi3B + absorbs almost 650mah), but is noticeably detached from the first RPi Zero W, which stops at around 125 mah and takes the podium if we consider the absolute numbers. In terms of performance, the new Pi 2 Zero W is an efficiency champion , outclassing its predecessors by a considerable margin and also breaking away from the relatively new Raspberry Pi 4B.

The Raspberry Pi Zero 2W. Source: RaspberryPi
The Raspberry Pi Zero 2W. Source: RaspberryPi

All this translates into a card suitable for projects that need to be battery powered but need more "brute force" than the Pi Zero W for faster calculations, or why not, to have fun with console title emulation. more modern. Furthermore, let's not neglect the compatibility of the CPU with 64bit code , which is establishing itself as the standard all over the world of computers; it is therefore also important for an SBC to ensure compatibility with software today and for years to come.

Where to buy it?

The Raspberry Pi 2 Zero is officially distributed in Italy by melopero.com, kubii.it and okdo.com at a price ranging between € 15.99 and € 16.90. At the time of writing, it is out of stock on all three platforms , possibly due to the global semiconductor famine that manufacturers are facing.

What hasn't changed?

Controversial point is the choice to include only 512MB of RAM, as in the previous model. According to the foundation, the limitation is due to the "system-in-package" technique used and we cannot expect a version of 1GB or more in the future , as happened for the Raspberry Pi 4.

This substantially limits the usage scenarios, especially in applications such as mini servers or if a graphical interface is required; we remember in fact that part of the RAM is used by the graphics processor and therefore we will hardly see this card in applications that are not headless , ie without a monitor.

2.4ghz WiFi

Recall that the W in the name stands for wireless, that is, it emphasizes the presence of WiFi and integrated Bluetooth, to distinguish it from the Raspberry Pi Zero (without W, that is, without wireless devices). A marginal upgrade to wireless components was made for this model to comply with a larger number of RF standards , but support for 5 ghz networks continues to be lacking. We will have to settle for the "tested" 2.4 ghz network.

Like the previous “Zero Ws”, the Pi Zero 2 W measures 65mm × 30mm and has the same ports and I / O components as the previous model:

  • Wi-fi 2.4 GHz IEEE 802.11b / g / n;
  • Bluetooth 4.2, Bluetooth Low Energy (BLE);
  • Micro-USB 2.0 On-The-Go (OTG);
  • Mini-HDMI;
  • Micro-USB for power supply;
  • GPIO 40 pin – HAT compatible
  • MicroSD card slot
  • CSI-2 camera / camera connector

Another sore point is the missed opportunity to update the USB ports with the new USB-C standard, more robust and widespread than the old micro-USB, as well as compatible with USB 3.0, still absent on the “Zero” line. To console us, thanks to this we will have full backwards compatibility with the accessories and cases of the previous model.

The competitors of the Raspberry Pi Zero 2W

One of the more interesting competitors is the Radxa Zero, introduced in June 2021 . It has a 1.8 ghz quad-core ARM Cortex-A53 processor and ARM Mali-G31 MP2 graphics. It promises performance comparable to 70% of that of a Raspberry Pi 4 and therefore even higher than that of the RPi Zero 2 W; moreover, it makes use of the new USB-C ports, one of which is compatible with USB 3.0 and boasts 4 configurations:

  • 512MB of RAM with WiFi 4 and Bluetooth 4 for $ 15
  • 1GB of RAM with WiFi 4 and Bluetooth 4 for $ 20
  • 2GB of RAM, 8GB of eMMC storage with WiFi 5 and Bluetooth 5 for $ 30
  • 4GB of RAM and 16GB of eMMC storage with WiFi 5 and Bluetooth 5 for $ 45

Distributed in Italy by Allnet Italia, where it is not yet available, in Germany by innet24.de and shop.maker-store.de where, however, it costs about € 10 more than the conversion from the dollar and finally in China by shop.allnetchina. cn where at the time of writing this article many models are out of stock.

Another competitor is the Banana Pi BPI-M2 ZERO, based on Quad-core Cortex-A7 CPU at 1 ghz , has 512 MB of RAM and the same form factor and layout as the small Raspberry. It ranks at the bottom of the league in terms of performance, having been created to compete with the first Raspberry Pi Zero. A treat: it has built-in power and reset buttons, a rarity on these cards. Produced by SINOVOIP and distributed on Taobao.com, Alibaba.com and aliexpress.com it has a variable price between € 15 and € 35 depending on the seller

Creative applications

With this powerhouse comes a great responsibility: putting it to use! Once the main limitation of the first has been overcome, with the Raspberry Pi Zero 2W we expect to see new handhelds capable of running the same emulators of the larger SBCs, robots capable of evaluating and reacting more quickly to the environment around them and more smart cameras. defined thanks to the computing power of these new mini SBCs.

The new Raspberry Pi Zero 2 W will not be revolutionary if you think of its existing competitors on the market but it represents a new point of reference for this format and for low-cost SBCs in general, thanks to a solid community and to the support guaranteed by the Raspberry P foundation i. Competitors such as the Radxa Zero show that this form factor can still be worked on and perhaps more daring, especially with respect to RAM capacity.

In any case, the general lack of availability of these cards highlights a wider problem and a nut to crack, that of the procurement of semiconductors, which has come to involve this sector as well.

Article by Francesco Porcelli

The article Raspberry Pi Zero 2W, a quad-core mini SBC for 15 € comes from Tech CuE | Close-up Engineering .