raspberry pi

Raspberry Pi Zero 2 powers the Null 2 RetroPie gaming handheld

As a kid, I never had a Game Boy, Game Gear, or any other handheld console. Heck, as luck would have it I've never owned a Nintendo Switch, either.

I've played console and PC games, I've only used handhelds twice: once in middle school, when a friend let me borrow his Game Gear for a day, and last year year when my dad brought over his Nintendo Switch—which my kids quickly commandeered.

I guess out of a sense of jealousy, I decided the first thing I should do with Raspberry Pi's latest hardware, the Pi Zero 2 (see my review here), is build myself a handheld retro gaming console.

Null 2 kit on Tindie

And what better way than with the Null 2 kit (pictured above, from it's Tindie page), a kit integrating off-the-shelf components on a custom PCB, wrapped up nicely in a custom acrylic case.

Look inside the Raspberry Pi Zero 2 W and the RP3A0-AU

Today, Raspberry Pi released their new Zero 2 W, and it includes a new Raspberry Pi-branded chip, labeled RP3A0-AU.

I was able to get early access to the Zero 2, and I have a full review of the device on my YouTube channel, but I wanted to share more of the X-ray images I took of the device to reveal its inner workings, and because I just think they look cool. Also, I paid a bit of money to get these pictures, so might as well share!

First, here's what the Zero 2 W looks like in person:

Raspberry Pi Zero 2 W

And here's what it looks like via X-ray:

Raspberry Pi Zero 2 W - X-ray vision

Kubesail's PiBox mini 2 - 16 TB of SSD storage on a Pi

Kubesail Raspberry PiBox mini 2 front side exposed

Many months ago, when I was first testing different SATA cards on the Raspberry Pi Compute Module 4, I started hearing from GitHub user PastuDan about his experiences testing a few different SATA interface chips on the CM4.

As it turns out, he was working on the design for the PiBox mini 2, a small two-drive NAS unit powered by a Compute Module 4 with 2 native SATA ports (providing data and power), 1 Gbps Ethernet, HDMI, USB 2, and a front-panel LCD for information display.

The Hardware

The PiBox mini 2 is powered by the Compute Module 4 on this interesting carrier board:

PiBox mini carrier board with Raspberry Pi Compute Module 4

Getting a Raspberry Pi to boot after cutting it in half

This blog post starts with the question: If I cut the ports off a Raspberry Pi 4 model B, will it still work?

Cut Raspberry Pi 4 model B

My early conclusion? Sorta.

With most Raspberry Pi generations, there is a full-featured model B, and a smaller, trimmed-down model A. The Pi 4 never had a model A, so I thought it would be interesting to see if I could make one. I looked at the Pi 4 with this really cool X-ray tool, as well as using this album of X-ray images from reddit user u/xCP23x:

Xray image of Raspberry Pi 4 model B

The cut was calculated to try to avoid anything important, though as we'll find later it may not have been measured carefully enough.

Automating the Uncommon - AnsibleFest 2021 presentation

At AnsibleFest 2021, I presented a session titled Automating the Uncommon - Ansible automates everything!.

Since watching on-demand versions of the AnsibleFest sessions requires a signup, I thought I'd also post the session to my YouTube channel, so everyone can learn from it without registering. The session seemed well-received, and I hope it shows that, as I state in my 'Rule of Golden Hammers':

Jeff's rule of Golden Hammers - If you know a tool well enough, and the tool is good enough, it's okay to do weird things with it.

I demonstrate how I use Ansible to:

Attaching to a Raspberry Pi's Serial Console (UART) for debugging

Sometimes a Pi just won't boot. Or it'll boot, but it'll do weird things. Or you don't have an HDMI display, and you can't log into your Pi via SSH. Or maybe you're like me, and someone 'accidentally' cut your Raspberry Pi in half, and you want to see what it's doing since it won't boot anymore.

Raspberry Pi with UART Serial Console Debug cable connected

The Raspberry Pi can output information over a 'serial console', technically known as a UART (Universal Asynchronous Receiver/Transmitter). Many devices—including things like storage controller cards, which in a sense run their own internal operating system on an SoC—have a 'UART header', which is typically three or four pins that can connect over the RS-232 standard (though many do not operate at 12v like a traditional serial port! Use a USB-to-TTL adapter like the one I mention below).

Simply Embedded has a great overview of UART if you want to learn more.

Face detection for my leaf blower

In the class of 'out there' projects, I recently added a little AI to my leaf blower:

Leaf blower with Raspberry Pi on top for AI ML Machine Vision blasting

The short of it: I have a face detection algorithm running which, when a certain individual enters the field of the Pi's vision, triggers a servo that powers on the blower, releasing a powerful air blast.

Red Shirt Jeff gets blasted by air cannon

I've been wanting to play around with face detection on the Pi for some time, but the Pi Zero I use in most of my camera projects is seriously underpowered for this kind of work.

CM4Ext Nano

So when Harlab (Hardware Laboratory) told me they'd like to send me a CM4Ext Nano board for testing, I thought it'd be the perfect opportunity to play with machine vision on the Pi.

Raspberry Pi 4 model Bs arriving with newer 'C0' stepping

Owing to a mishap with the Pi 4 model B I use for testing—more on how Red Shirt Jeff ruined that board later this week—I had to go buy a new Pi 4 last week.

The local Micro Center only had the 8 GB model in stock, so I went a little over budget and bought it. When I arrived home, I checked the board, and noticed a bit of a difference on the Broadcom SoC:

Raspberry Pi 4 model B C0 stepping on BCM2711 SoC

Can you spot it? The model number of the BCM2711 chip on this board is 2711ZPKFSB06C0T, which is the same as the chip found on the Pi 400.

This is a newer stepping of the original Pi 4 model B chip, which has the model number 2711ZPKFSB06B0T. The difference is the third-to-last character, the C versus the B.

Raspberry Pi KVMs compared: TinyPilot and Pi-KVM v3

In a strange coincidence, the authors of TinyPilot and Pi-KVM both emailed me within a week of each other and asked if I'd be interested in one of their KVM devices.

TinyPilot vs Pi-KVM v3 Price comparison

Michael Lynch, founder of Tiny Pilot, said he'd used some of my Ansible work in building the TinyPilot update system, and Maxim Devaev, of Pi-KVM, liked my Pi open source content, and wanted to see what I thought of the new v3 kit that's currently on Kickstarter.

I took them both up on the offer, and dug into both devices.

Both have HDMI and USB inputs, so you can plug them into any Mac or PC and get full control, up to and including BIOS/UEFI settings, remote desktop management (with no software on the managed computer), and mounting of USB ISO images for re-installing an OS or maintaining a system.

Monitoring my home's air quality (CO2, PM2.5, Temp/Humidity) with AirGradient's DIY sensor

A few months ago, I found this Hacker News post about the AirGradient DIY Air Quality Monitor. I had already been considering buying an AirThings Wave Plus sensor to monitor my home's CO2 levels, but the high price and limited 'ownership' of the data coming from it turned me off.

AirGradient DIY Air Quality Sensor - Focus Stacked by Jeff Geerling

So I built two AirGradient DIY air quality monitor boards (see above), and integrated them into my Prometheus + Grafana home monitoring setup I've been using to monitor other things in my house:

AirGradient DIY Grafana Dashboard for CO2 PM2.5 Temperature Humidity monitoring