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4GB Raspberry Pi 4 Model is Out of Stock

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raspberry-pi4-specs
Raspberry Pi 4

Wow, demand for the latest and greatest Raspberry Pi 4 is bigger than I thought! I didn't want to order it right when Raspberry Pi 4 was announced, and will have to wait a few weeks now until all the pre-orders are fulfilled.

Why Raspberry Pi 4 Model with 4GB is Most Popular

I belive Raspberry Pi 4 with 4GB RAM is the closest yet to a fully functional desktop system: you can develop software, test and host websites, setup your own cloud systems and even play games like Minecraft with the smoothest experience.

I also think Raspberry Pi 4 is still pretty cheap, so the extra eur10-20 you will pay to get more powerful model is well worth the relatively dramatic gains from such an upgrade.

Finally, dual monitor setup with 4K resolutions is another very tempting feature of the Raspberry Pi 4 – and while it's available on all the latest models, I think the 4GB version is most popular because users plan to run more applications and more advanced software development setups with extra memory available.

ModMyPi, the vendor I used to get everything Raspberry Pi from, has just been purchased by ThePiHut company – and their website shows Raspberry Pi 4 with 4GB out of stock. Hope this is not for long as I really want to get the latest model for some experiements in my Unix Tutorial Hardware Lab.

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Unix Fun: cowsay command

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Screen Shot 2019-06-10 at 12.16.32.png

cowsay is a comman line tool that you can install on any Linux or Unix distro to render funny text updates as if they're told by a cute text mode cow. There are lots of options to customise the look of both the cow and the text message.

Installing cowsay in Raspbian OS

I decided to install cowsay on one of my Raspberry Pi systems at home:

greys@becky:~ $ sudo apt install cowsay
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
lxkeymap python-cairo python-gtk2 python-xklavier
Use 'sudo apt autoremove' to remove them.
The following additional packages will be installed:
cowsay-off
Suggested packages:
filters
The following NEW packages will be installed:
cowsay cowsay-off
0 upgraded, 2 newly installed, 0 to remove and 182 not upgraded.
Need to get 27.9 kB of archives.
After this operation, 114 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://ftp.heanet.ie/mirrors/raspbian/raspbian stretch/main armhf cowsay all 3.03+dfsg2-3 [20.1 kB]
Get:2 http://ftp.heanet.ie/mirrors/raspbian/raspbian stretch/main armhf cowsay-off all 3.03+dfsg2-3 [7,816 B]
Fetched 27.9 kB in 0s (60.1 kB/s)
Selecting previously unselected package cowsay.
(Reading database ... 211819 files and directories currently installed.)
Preparing to unpack .../cowsay_3.03+dfsg2-3_all.deb ...
Unpacking cowsay (3.03+dfsg2-3) ...
Selecting previously unselected package cowsay-off.
Preparing to unpack .../cowsay-off_3.03+dfsg2-3_all.deb ...
Unpacking cowsay-off (3.03+dfsg2-3) ...
Setting up cowsay (3.03+dfsg2-3) ...
Setting up cowsay-off (3.03+dfsg2-3) ...
Processing triggers for man-db (2.7.6.1-2) ...

Using Cowsay in Linux

Just type "cowsay" followed by a few words and you'll get something like this:

Screen Shot 2019-06-10 at 11.12.51.png

Changing the cow appearance in cowsay

From the cowsay man page:

There are several provided modes which change the appearance of the cow depending on its particular emotional/physical state. The -b option initiates Borg mode; -d causes the cow to appear dead; -g invokes greedy mode; -p causes a state of paranoia to come over the cow; -s makes the cow appear thoroughly stoned; -t yields a tired cow; -w is somewhat the opposite of -t, and initiates wired mode; -y brings on the cow's youthful appearance.

Here's an example of one of these options:

Screen Shot 2019-06-10 at 11.19.50.png

It's also possible to just specify the charecters to be used for the eyes of the cow, -e option needs to be followed by the two characters you want to seeScreen Shot 2019-06-10 at 12.14.51.png:

That's it for today, it's been fun!

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Advanced Hardware Information for Raspberry Pi

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Screen Shot 2019-06-02 at 23.59.26.png

I've just learned about a really cool command for Raspbian OS, available in recent (Debian 9.0 based and later) Raspbian OS releases: pinout command shows you a visual presentation of what hardware configuration your Raspberry Pi has.

Simply type pinout, you don't even need to use sudo. You'll see output consisting of 3 parts that are so visual that I'll screenshot two of them to show you exactly what to expect.

Pinout command for Rasbian OS – Raspberry Pi schematics

First part of the otuput looks really cool – it shows you the model name and the system board layout – where power and HDMI connections, where Ethernet port is and where to plug in USB:

Screen Shot 2019-06-02 at 23.57.00.png

Then you get the second part of the output, which is additional hardware info about your Raspberry Pi:

Revision : a01041
SoC : BCM2836
RAM : 1024Mb
Storage : MicroSD
USB ports : 4 (excluding power)
Ethernet ports : 1
Wi-fi : False
Bluetooth : False
Camera ports (CSI) : 1
Display ports (DSI): 1

Finally, the last part of the output of the pinout command is actually the pinouts layout for the GPIO part of Raspberry Pi plaform:

Screen Shot 2019-06-03 at 00.09.18.png

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