Welcome to the third of six blog posts in support of the Raspberry Pi Zero 2W Roadtest. The blog posts will explore different aspects of the product while attempting to engage the E14 Community members. Comments and questions to the blog posts are welcomed and encouraged. The blog posts will serve as the resources for assembling the RoadTest Review document.
The project objective is to pair a Raspberry Pi Zero 2W with a camera, assemble it on a HO scale model railroad car with a power source and stream or record video of the train in motion.
A while back, I attempted to produce video content using a Pi3B+. I discovered that the Raspberry Pi operating system (O/S) Bullseye, transitioned from the legacy camera software stack based on proprietary Broadcom GPU code to an open-source stack based on libcamera. Raspberry Pi OS images from Bullseye onward will contain only the libcamera-based stack.
My limited knowledge of the legacy camera would need to be upgraded if I was to proceed. I wasn't ready for that upgrade, so I abandoned the project of producing video. To create an application that would hopefully wow the RoadTest selection committee, I pitched this Riding-the-Rails camera project. Now I have a reason to invest in the camera knowledge upgrade.
In preparation for the review, I researched some resources on the product and made the links available.
Bill of Materials
-PiZero2W
-32GB SD Card
-Raspberry Pi OS Lite, Release date: January 28th 2022, System: 32-bit, Kernel version: 5.10, Debian version: 11 (bullseye)
-Camera V1.3 & V2.1
-4500mAmp/hr lithium battery
-Model:28BYJ-48 stepper motor with ULN2003 Stepper Motor Driver Board Module
-SG90 9g 4.8-6V 180 Degree Mini Analog Servo Smart
(The RoadTest supplied equipment included a Cankit model DCAR-052A5 wall-wart power supply. The specification indicates 5V 2.5amp. It has a little weight to it. Much better than a few cheap knock-off power supplies I have tried. This power supply will be used during project development, with the final power being provided by a batter source.)
Unboxing
The UPS package from E14 arrived with all contents undamaged. The SD card and PiZero2W were packaged in antistatic bags and the power supply in a manufactures box. A self-adhesive heat sink for the Pi was also provided.
Silkscreen labeling on the back of the Pi motherboard indicates Raspberry Pi Zero 2, Raspberry Pi 2021. Hmmm, I confirmed there is no W suffixed on the silkscreen Pi name. RoadTest says Raspberry Pi Zero 2W. Looks like confirmation is needed. I will provide more details of the internals of the Pi once an operating system is installed. Those details will be included in a later blog.
Raspberry Pi Zero Chronology
| November 2015: Raspberry Pi Zero with smaller size and reduced input/output (I/O) and general-purpose input/output (GPIO) capabilities was released. |
| February 2017: Raspberry Pi Zero W was launched, a version of the Zero with Wi-Fi and Bluetooth capabilities. |
| January 2018: Raspberry Pi Zero WH was launched, a version of the Zero W with pre-soldered GPIO headers. |
| October 2021: Raspberry Pi Zero 2 W was launched, a version of the Zero W with a system in a package (SiP) designed by Raspberry Pi and based on the Raspberry Pi 3. In contrast to the older ones, the Pi 2 W is 64 bit capable. |
PiZero2W Specification
1GHz quad-core 64-bit Arm Cortex-A53 CPU
512MB SDRAM
2.4GHz 802.11 b/g/n wireless LAN
Bluetooth 4.2, Bluetooth Low Energy (BLE), onboard antenna
Mini HDMI port and micro USB On-The-Go (OTG) port
microSD card slot
CSI-2 camera connector
HAT-compatible 40-pin header footprint (unpopulated)
H.264, MPEG-4 decode (1080p30); H.264 encode (1080p30)
OpenGL ES 1.1, 2.0 graphics
Micro USB power
Composite video and reset pins via solder test points
PiZeroW Specification
1GHz, single-core CPU
512MB RAM
802.11 b/g/n wireless LAN
Bluetooth 4.1
Bluetooth Low Energy (BLE)
CSI camera connector
Mini HDMI port and micro USB On-The-Go (OTG) port
Micro USB power
HAT-compatible 40-pin header
Composite video and reset headers
PiZero Specification
1GHz single-core CPU
512MB RAM
CSI camera connector (v1.3 only)
Mini HDMI port
Micro USB OTG port
Micro USB power
HAT-compatible 40-pin header
Composite video and reset headers
Raspberry Pi Hardware schematics and mechanical drawings
Power Supply
| Product | Recommended PSU current capacity | Maximum total USB peripheral current draw | Typical bare-board active current consumption |
| Raspberry Pi Zero | 1.2A | Limited by PSU, board, and connector ratings only | 100mA |
| Raspberry Pi Zero W/WH | 1.2A | Limited by PSU, board, and connector ratings only. | 150mA |
| Raspberry Pi Zero 2 W | 2A | Limited by PSU, board, and connector ratings only. | 350mA |
The next blog post will be Riding-the-Rails with a Raspberry Pi Zero 2W: Operating System Install & Configuration. I will document the approach I use to load the Raspberry Pi and operating system and make configuration changes to establish the base. The camera software configuration will be a separate blog post.
See you at the next stop.