Richard's Tech Reviews

if using Make Minecraft do not update Kano

UPDATE 2018-11-02: The information below is from December 2016.  It is no longer relevant to try to keep Kano at version 3.7.0  END UPDATE

I installed Kano OS 3.7.0 on a Raspberry Pi 3B

https://downloads.kano.me/public/Kanux-Beta-v3.7.0-jessie-release_noobs.zip

On first run it has several updates (to beta 3.8.0), which take a long time to run.  If you want to keep Make Minecraft DO NOT UPDATE Kano OS to 3.8.0 at this time.

The most significant update I noticed is a total replacement of Make Minecraft with Hack Minecraft.

The underlying concept of learning by using a block-based programming language remains, but the tasks are different, and there doesn't appear to be any way to easily see the Python code.  To me that was the most useful part of the exercise, to be able to show that the blocks created specific computer code.  Plus which, if you were part-way through Make Minecraft, all your tasks and progress are gone.

Also the tasks are a bit flaky.  The write your name one didn't work for me the first time I tried, and the second time it showed a black screen - I had to tab into Minecraft and look in a different direction to see the name blocks. Plus which the blocks for the letter S appear to be wrong.

It looks to me like Hack Minecraft is a replace of /usr/share/make-minecraft ; the original executable and scripting code is completely replaced with Hack Minecraft.

This is not cool to do without any warning.  You might want to backup your make-minecraft directory just in case (e.g. make a copy of it using cp -r, if you're familiar with using the command line).

I have posted on Kano World Forum asking for more information but this is probably useless as Forum is no longer maintained.  You're supposed to email [email protected] instead.

Ideally Hack Minecraft should be a separate install in /usr/share/hack-minecraft with a default to duplicate world(s) from ~/.minecraft/ (the user's home directory contains the user's Minecraft worlds)

Make Minecraft

• comes with Kano OS 3.7.0
• runs from /usr/share/make-minecraft/bin/make-minecraft
• can easily display the Python code that is being generated from the block programming interface

Hack Minecraft

• installed with an update to Kano OS 3.8.0
• runs from /usr/share/make-minecraft/www/index.html ??? (JavaScript)
• no way to see code generated from block programming interface

3.7.0 to 3.8.0

There are other differences as well.  The most significant is that instead showing just a few coding and entertainment related apps in Home (Make & Explore) and grouping everything else inside of "Kano Apps", in 3.8.0 all the apps are listed out page after page.  For young children this may not be ideal.

Kano OS beta 3.7.0 on Raspberry Pi 1B 256MB

Kano - Developers - Downloads for Kano OS beta 3.7.0 says "Runs on Raspberry Pi 1B, 2, 3 and Zero".  Which is true except there is a subtlety about the 1B.  There were actually two models of the 1B: an early model with 256MB RAM, and a later model with 512MB RAM.  This turns out to be important.

The boot config for 3.7.0 assumes the 1B has 512MB, and if you run it on the 256MB it will more or less hang once it gets to the graphics environment.  You may see a mouse pointer and nothing else, forever, or see it partly start up the graphics environment and then nothing.

I thought it might be RAM related so I looked at the config.txt

You can do this by e.g. reading the SD card on a Mac and examining config.txt on the boot partition.  (Note that you should only edit this file with a text editor such as BBEdit, not with a word processor.)

The default config.txt says

# set memory split: amount allocated to the GPU in MB.
gpu_mem=128

This is clearly way too high for a 256MB Pi 1B. I changed it to

gpu_mem=32

and then Kano OS booted up fine. top shows about 16MB free, so the capacity to run apps may be fairly limited, but you can at least see the graphic environment (GUI) and open a terminal windows etc.

You will want to wait a while for initial startup tasks to complete.  When startup is running the CPU will be close to 100%.  It should drop to around 40% once startup is completed.

Note: once you're able to actually load a terminal (e.g. K->Code->Terminal or Apps icon - CODE - Terminal) you can find config.txt in /boot/config.txt

I will do further experimentation, and see whether 32MB GPU RAM makes a usable environment or whether a 16MB allocation works better.

The OS will complain at boot time if you set GPU RAM to 16MB, but it will boot.  top will rather unsurprisingly show 32MB free rather than 16MB.

I was unsuccessful in getting Make Minecraft to run in either 32MB or 16MB configuration.  In 32MB configuration it froze, in 16MB configuration it tried to launch Minecraft but then crashed and closed.

I will make a list of what software works and what doesn't.  Development of list in progress.

Works with GPU 16MB RAM:

• Scratch

Does not work:

• Make Minecraft (crashes at Minecraft launch)