Raspberry Pi
XTEInk X4
Raspberry Pi USB Gadget
Back in 2019 I learned about and testing using a Raspberry Pi as an accessory to an iPad. The idea is useful for people who want a local Linux terminal on an iPad rather than making a remote connection to one on a server. People who use terminal apps like vi or emacs and developer tools are the ones who find this the most useful.
The process involves connecting a Raspberry Pi to an iPad via USB-C cable, and software on the Raspberry Pi make the USB-C connection function like an ethernet network connection. You get an IP address that you can use to login to the Pi using SSH, at which point then have access to all the tools available in the Raspberry Pi OS. If a VNC Server is running on the Pi you can even get a desktop connect using a VNC Viewer.
The instructions for setting this all up,, in which is called USB Gadget Mode, are not daunting but take a little bit of work. Today I learned that the functionality for USB Gadget Mode is now available directly in the Raspberry PI OS.
I’ve written before about how the then low cost Timex Sinclair 1000 personal computer was so influential on my life. Today’s equivalent to the Timex Sinclair is the Raspberry Pi, and I don’t think it’s coincident it also originates from England. In my opinion a Raspberry Pi should be provided to every young kid, particularly if they have any interest with computers. The newest model has just been announced and will start shipping at the end of October, you can pick up an 8 GB model with case and power supply for just over $102.
Reading an article written by the folks at raspberrypi.com about why they set up their own Mastodon instance, and I find the following statement interesting and compelling. It goes on to state how their DNS registrar effectively provides verification that they are who they are.
We’ve opted to host our own instance. We’ve done this because, with multiple instances out there, we had to decide how to make sure people following us knew that our Raspberry Pi account was the “real” one.
Yesterday I had a Raspberry Pi crash after a system update and fail to boot. I figured out what went wrong and learned some things along the way. Breaking things is how one tends to learn.
Happy Windows 11 day! I’ve spent the last several days experimenting with the ARM Version of Windows 11 on a Raspberry Pi 4. The installation process is pretty easy thanks to the WoR-Flasher utility, which I used to “burn” an installation image to a SSD. At first I tried installing by simply using USB drive, and while that worked I wondered whether using a SSD would be better. I ended up buying an inexpensive Crucial SSD and a 3.1 USB enclosure, which isn’t going to be as fast a direct PCIe connection, but the combo does time out faster than the thumb drive. One challenge I had was making sure the power adapter of the Pi was providing enough power for the drive, which I resolved once I used the 3.5A USB C power adapter from CanaKit. One constraint is that the Windows 11 build does not work with the Pi 4’s WiFi. I don’t know how long this version of Windows 11 will last, from what I read the update process is not smooth and may require a re-build, which will wipe out a product activation.
During this process I learned about differences between SATA and NVME SSD drives and found a really helpful guide about the Pi 4 bootloader and USB mass storage. I also found a very extensive site of performance benchmarks of mass storage connected to Raspberry Pis.
Learning Computing
Back when there were several book store chains and plenty of stores I spent a fair amount of time in them and in particular looking through the computer magazine section. Magazines were a big part of my formative computing years, and I looked forward to each month’s issue of Byte. The magazines were not only a source of news about the latest hardware and software, they were also a means of software distribution containing pages of source code available to manually enter on a variety of computer platforms.
Physical book stores are nearly extinct and computer magazines shrank in to oblivion, replaced by the Internet, but I have found one corner of the Internet where computer magazines still live. You may have heard of the Raspberry Pi, which is an inexpensive “computer on a chip” popular amongst makers. What you might not know is that raspberrypi.org is more than just the computer hardware, it’s a foundation dedicated towards computer education. The foundation publishes tutorials and lesson plans for teachers and it has a publishing arm for books and magazines.
Four different magazines are published: HackSpace, Custom PC, Wireframe, and The MagPi, which you can subscribe to and purchase online and in stores in the United Kingdom. Better yet, the magazines and books are free to download in PDF format.
If you own a Raspberry Pi and have the full desktop version of the operating system installed you will find a Bookshelf app in the Help menu of the desktop’s application launcher. Bookshelf has tabs for each magazine and books that you can download and read on the Pi. If you don’t have a Pi you can browse through and download the PDFS using the web browser on your computer.
If you are not familiar with Raspberry Pi you will find everything you need to know about it on their web site, raspberrypi.org. Another great source for information is the Official Raspberry Pi Handbook, and the 2022 version has been just released and available to download.
If you are looking for an inexpensive starter computer for yourself or a child, I recommend the Raspberry Pi 400, which is an “all-in-one” computer you can buy for $70. I also think anyone considering a future in computing, or just interested to learn more, should buy a Raspberry Pi 4 kit, which you can assemble and use to learn more about computer hardware and software.
Home Computer Repairs
Given the number of Raspberry Pis I have, you might get the impression that I am a maker, but I am not. I’ve just been enamored by these small, inexpensive single board computers. The closest I’ve come so far to a real project is what I call my desk clock, which is a Pi installed behind a five inch monitor that displays Chromium kiosk mode with a screen I configure using Dakboard.
I originally built the desk clock using a Raspberry Pi 2 that stopped working a few weeks ago. This past weekend tried to troubleshoot the problem. First I built a new SD card and it seemed to boot fine, but after a few more tests I found that the USB WiFi dongle was not reliably connecting to the home network, so I decided to re-purpose a Pi 3 that was on my desk for the desk clock.
To retain the backup and archive functions that Pi 3 was performing, I moved it’s SD card to a Pi 3b+ and then built a new SD card for the desk clock, except this time I cheated by using a pre-built image that dakboard provides.
The net result is that I now have one less Raspberry Pi sitting on my desk. Last night as I was putting things away I found another Pi 3 I already had been storing, which if I had known about would have simplified things, but not resulted in one less Pi on my desk.
For a summary of my Raspberry Pis, expand the Every Day Tech branch of my Technology outline.
Recently I was describing the Raspberry Pi 400 to my wife by asking her if she remembered the Commodore 64 because the Pi 400 is basically a keyboard with a computer beneath. I told her that for nostalgia purposes I was interested in the Pi 400, but frankly I am not sure how I would use it. It really doesn’t make sense to use the Pi 400 headless like I do my other Raspberry Pis.
All this is preamble to point you to my retro computer that sells a case that looks nearly identical to the old C-64.
Overclocking A Raspberry Pi 4
I am using a Raspberry Pi 4 (daenerys) as my desktop personal computer during the work day, which I access from my work provided computer using VNC. By using this Pi 4 I can access the Internet from my desk without going through the corporate Internet proxy.
I built daenerys in a Flirc case, which looks really nice and provides passive cooling, and it boots from a SSD in an Inateck case. The SSD gets power from the Pi and so under normal load I would see temperatures hover around 55 degrees celcius, which is well below the 85 degree threshold that causes the CPU to throttle down.
Over the holiday I built another Raspberry Pi 4 (arya) in a MazerPi case that has a fan. The fan draws power from the GPIO pins and has two modes, high speed if plugged in to the 5v pin (PIN 2) and low speed if plugged in to the 3.3v pin (PIN1). To complete the picture, ground is plugged in th PIN 6.
The MazerPi fan just stays on all the time, I am not aware of a way to control the fan so that it only comes on when a certain temperature threshold is past. I first plugged the fan in to one of the 5v pins and found it loud enough to be heard, although not terribly loud. When using high speed mode the CPU temperatures were in the mid to high 30 degree range under normal load. When I ran Octane 2 it then crossed 40 degrees.
I decided to try the low speed mode, which is quiet enough to not hear unless one concentrates. Temperatures where in the 40 to 45 degree range, which is plenty good.
At this point the thought occurred to me that it probably makes sense to use the case with the fan for the Pi that I am going to use every day rather than in one I am going to use as an accessory and thus I removed the SD card from arya and plugged in the SSD from daenerys and it booted right up. (BTW, note that in reality a computer host name is associated with the boot drive and not the actual computer, so daenerys is really the 250 GB SSD drive while arya is a 256 GB SD card.)
Finally, I decided I wanted to try overclocking daenerys, which given the fan should be safe. Normal speed for this Pi4 board is 1.5 GHz, so I decided to overclock it to 2 GHz. Performance is noticably faster. At 1.5 Ghz daenery’s Octane 2 score is 8098 and at 2.0 Ghz the score is 9777. Neither score is fantastic, but good enough for the type of web browsing that I do.
When you overclock a CPU it will run hotter and that can cause failures. In the MazerPi, with the fan in low speed mode, and the Pi 4 booting from a SSD and overclocked to a max frequency of 2 GHz and a minimum frequency of 1 GHz I am seeing temperatures ranging from 46 degrees to 55 degress, which is about the same as well using the Pi in the Flirc case but not overclocked.
The net result is that have “upgraded” daenerys to a faster processing speed that provides better performance while maintaining a good CPU temperature and so far after one full working day it has been stable. The MazerPi case cost only $8 and is easy to assemble with help from a video I found on YouTube.